CVE-2026-106450

yawkat LZ4 Java provides LZ4 compression for Java. Prior to 1.11.4, net.jpountz.lz4.LZ4FrameInputStream readHeader() allocates two new 4 MiB block buffers whenever a maximum-block-size frame header is read, and the default concatenated-frame mode allows attacker-controlled streams containing many minimal empty frames to trigger roughly 8 MiB of allocation for every 11 input bytes. The stream produces no decompressed output while consuming CPU and garbage-collection time, so decompressed-size limits do not mitigate the issue; readSingleFrame mode is not affected. This issue is fixed in version 1.11.4.

• https://github.com/yawkat/lz4-java/commit/2acc0ec1ead226145c62a817c18c8ed49233a283
• https://github.com/yawkat/lz4-java/releases/tag/v1.11.4
• https://github.com/yawkat/lz4-java/security/advisories/GHSA-gm45-99xc-r7wv