What’s Vulnerable › Vulnerabilities

CVE-2026-106453: yawkat LZ4 Java: LZ4DecompressorWithLength allocates the unvalidated size from the 4-byte length header, so a 5-byte input triggers a 1 GiB allocation and OutOfMemoryError

• Severity: medium (CVSS 5.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-06 · updated 2026-10-07
• Weakness: CWE-789

Description

yawkat LZ4 Java provides LZ4 compression for Java. Prior to 1.11.2, LZ4DecompressorWithLength uses getDecompressedLength to trust the four-byte decompressed-length header before validating the compressed input, allowing a five-byte attacker-supplied input whose header declares a large output size to request up to approximately 2 GiB and exhaust the JVM heap. Convenience overloads backed by LZ4FastDecompressor or LZ4SafeDecompressor allocate the untrusted size, while overloads that write to a caller-provided destination buffer are not affected because the caller controls the destination size. This issue is fixed in version 1.11.2.

Affected products

• yawkat lz4-java: before 1.11.2

References

• https://github.com/yawkat/lz4-java/commit/6492ce5aca6bd03ff9e08ee18a2beb94c431371a
• https://github.com/yawkat/lz4-java/releases/tag/v1.11.2
• https://github.com/yawkat/lz4-java/security/advisories/GHSA-6cx8-rjf8-pr8g

Get alerted when CVE-2026-106453 or the next vulnerability affects your stack