CVE-2025-31115 - CVE House
Back to Database
Status published High CVE-2025-31115

XZ has a heap-use-after-free bug in threaded .xz decoder

Vulnerability Description

XZ Utils provide a general-purpose data-compression library plus command-line tools. In XZ Utils 5.3.3alpha to 5.8.0, the multithreaded .xz decoder in liblzma has a bug where invalid input can at least result in a crash. The effects include heap use after free and writing to an address based on the null pointer plus an offset. Applications and libraries that use the lzma_stream_decoder_mt function are affected. The bug has been fixed in XZ Utils 5.8.1, and the fix has been committed to the v5.4, v5.6, v5.8, and master branches in the xz Git repository. No new release packages will be made from the old stable branches, but a standalone patch is available that applies to all affected releases.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

THREAT MONITOR

Am I Vulnerable?

Launch our assessment wizard to check if your infrastructure is exposed to • CVE-2025-31115

Credits & Attribution

No credits recorded in the NVD database.

Affected Vendor

tukaani-project

View all reports →

Affected Software

xz
Vulnerable Versions:
>= 5.3.3alpha, < 5.8.1

Timeline

Official Publish: April 3rd, 2025
Last Modified: July 14th, 2026
Added to House: July 22nd, 2026

CVSS Vectors