PT-2026-29689 · Tukaani · Xz

Christos-Spearbit · Published 2026-04-02 · Updated 2026-04-02 · CVE-2026-34743

Mitre

CVSS v4.0

1.7

Low

AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U

XZ Utils provide a general-purpose data-compression library plus command-line tools. Prior to version 5.8.3, if lzma index decoder() was used to decode an Index that contained no Records, the resulting lzma index was left in a state where where a subsequent lzma index append() would allocate too little memory, and a buffer overflow would occur. This issue has been patched in version 5.8.3.

Fix

Heap Based Buffer Overflow

Weakness Enumeration

CWE-122

Related Identifiers

CVE-2026-34743

Affected Products

Xz

References · 6

• https://nvd.nist.gov/vuln/detail/CVE-2026-34743 · Security Note
• https://github.com/tukaani-project/xz/security/advisories/GHSA-x872-m794-cxhv · Note
• https://github.com/tukaani-project/xz/releases/tag/v5.8.3 · Note
• https://github.com/tukaani-project/xz/commit/c8c22869e780ff57c96b46939c3d79ff99395f87 · Note
• https://twitter.com/oss_security/status/2039551983070134774 · Twitter Post
• http://openwall.com/lists/oss-security/2026/03/31/13 · Note