CVE-2026-106451yawkat LZ4 Java: Native library extraction to a shared temporary directory is vulnerable to file replacement by another local user

yawkat LZ4 Java provides LZ4 compression for Java. From 1.7.0 until 1.11.4, net.jpountz.util.Native.load() uses File.createTempFile to create an exclusive temporary .lck file but derives the native-library path by removing the suffix, then FileOutputStream opens that predictable path without exclusive creation, allowing another local user with access to the same shared temporary directory to create or replace the library file before System.load() uses it. Successful exploitation depends on shared-directory permissions, host protections, and winning the race, and can execute native code as the victim; hardened systems may instead cause library loading to fail and fall back to Java implementations. Configurations using a system library, a private java.io.tmpdir, or Java-only implementations are not affected. This issue is fixed in version 1.11.4.

CVSS

7.3 HIGH (v4.0, CNA)CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Weakness (CWE)

CWE-367, CWE-377

Known exploited

Not in CISA's KEV catalog

EPSS (exploitation in the next 30 days)

0.08% (percentile 0)

Assigned by

GitHub_M

NVD analysis

Awaiting Analysis

Record last updated

Oct 7, 2026

First seen by InfoSec Signals

Oct 9, 2026

The CVE record on cve.org · NVD's entry

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