diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java b/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java
index a360ea00773..a4d2e8b3901 100644
--- a/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java
+++ b/lucene/backward-codecs/src/test/org/apache/lucene/index/TestBackwardsCompatibility.java
@@ -439,6 +439,8 @@ public class TestBackwardsCompatibility extends LuceneTestCase {
       "5.5.3-nocfs",
       "5.5.4-cfs",
       "5.5.4-nocfs",
+      "5.5.5-cfs",
+      "5.5.5-nocfs",
       "6.0.0-cfs",
       "6.0.0-nocfs",
       "6.0.1-cfs",
diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.5.5.5-cfs.zip b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.5.5.5-cfs.zip
new file mode 100644
index 00000000000..063deb8ae29
Binary files /dev/null and b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.5.5.5-cfs.zip differ
diff --git a/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.5.5.5-nocfs.zip b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.5.5.5-nocfs.zip
new file mode 100644
index 00000000000..23203e2f22d
Binary files /dev/null and b/lucene/backward-codecs/src/test/org/apache/lucene/index/unsupported.5.5.5-nocfs.zip differ