CVE-2026-34743

medium

Description

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.

References

https://github.com/tukaani-project/xz/security/advisories/GHSA-x872-m794-cxhv

https://github.com/tukaani-project/xz/releases/tag/v5.8.3

https://github.com/tukaani-project/xz/commit/c8c22869e780ff57c96b46939c3d79ff99395f87

http://www.openwall.com/lists/oss-security/2026/03/31/13

Details

Source: Mitre, NVD

Published: 2026-04-02

Updated: 2026-04-15

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Severity: Medium

CVSS v3

Base Score: 5.3

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Severity: Medium

CVSS v4

Base Score: 6.3

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.00042