CVE-2025-31115CWE-366CWE-416CWE-476CWE-826

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

High · published April 3, 2025

CVSS v4.0
8.7
EPSS
1%
Percentile
51.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
8.7 · HIGH
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
EPSS
0.00662 · 51.1th percentile
Weaknesses
CWE-366 · Race Condition within a Thread; CWE-416 · Use After Free; CWE-476 · NULL Pointer Dereference; CWE-826 · Premature Release of Resource During Expected Lifetime
Published
2025-04-03T16:57Z
EPSS history
Timeline
  • 03 APR 16:57Z
    XZ has a heap-use-after-free bug in threaded .xz decoder
    cvelistv5