CVE-2025-66566: yawkat LZ4 Java has a possible information leak in Java safe decompressor

December 5, 2025

Insufficient clearing of the output buffer in Java-based decompressor implementations in lz4-java 1.10.0 and earlier allows remote attackers to read previous buffer contents via crafted compressed input. In applications where the output buffer is reused without being cleared, this may lead to disclosure of sensitive data.

JNI-based implementations are not affected.

References

github.com/advisories/GHSA-cmp6-m4wj-q63q
github.com/yawkat/lz4-java
github.com/yawkat/lz4-java/commit/33d180cb70c4d93c80fb0dc3ab3002f457e93840
github.com/yawkat/lz4-java/security/advisories/GHSA-cmp6-m4wj-q63q
nvd.nist.gov/vuln/detail/CVE-2025-66566

Code Behaviors & Features

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