Time-of-check Time-of-use (TOCTOU) Race Condition in lz4-java - #VU153027
Published: September 30, 2026
Vulnerability identifier: #VU153027
CSH Severity: Low
CVSS v4: 7.3 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-367
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to execute arbitrary code as the victim process.
The vulnerability exists due to a time-of-check time-of-use race condition in net.jpountz.util.Native.load() when extracting the bundled native library to java.io.tmpdir. A local user can create and replace the predictable native library file before it is loaded to execute arbitrary code as the victim process.
Exploitation requires a shared writable temporary directory, host settings that permit file replacement, and winning a race.
Affected software
lz4-java
Remediation
Install security update from vendor's website.
lz4-java - update to 1.11.4