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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-34743 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
CVSS-BT 1.7 LOW
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/E:U

References to Advisories, Solutions, and Tools

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

Weakness Enumeration

CWE-ID CWE Name Source
CWE-122 Heap-based Buffer Overflow GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

7 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-34743
NVD Published Date:
04/02/2026
NVD Last Modified:
07/24/2026
Source:
GitHub, Inc.