CVE-2026-34743

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/tukaani-project/xz/commit/c8c22869e780ff57c96b46939c3d79ff99395f87	Patch
https://github.com/tukaani-project/xz/releases/tag/v5.8.3	Product Release Notes
https://github.com/tukaani-project/xz/security/advisories/GHSA-x872-m794-cxhv	Vendor Advisory
http://www.openwall.com/lists/oss-security/2026/03/31/13	Mailing List Patch Third Party Advisory
https://lists.debian.org/debian-lts-announce/2026/07/msg00034.html

Configurations

Configuration 1 (hide)

cpe:2.3:a:tukaani:xz:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-02 19:21

Updated : 2026-07-24 21:10

NVD link : CVE-2026-34743

Mitre link : CVE-2026-34743

CVE.ORG link : CVE-2026-34743

JSON object : View

Products Affected

tukaani

xz

CWE

CWE-122

Heap-based Buffer Overflow

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