XZ Utils: Buffer overflow in lzma_index_append()_CVE-2026-34743

1.7 / 10

LOW

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

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.

Basic Information

ID CVE-2026-34743

Source GitHub_M

Published Apr 2, 2026 at 18:36

Modified Apr 3, 2026 at 12:59

Affected Product

Vendor tukaani-project

Product xz

Version < 5.8.3

Affected Versions tukaani-project xz < 5.8.3

CWE Classification

CWE-122

References

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    "published": "2026-04-02T18:36:37.450Z",
    "modified": "2026-04-03T12:59:06.096Z",
    "type": "cve",
    "title": "XZ Utils: Buffer overflow in lzma_index_append()",
    "source": "GitHub_M",
    "references": "https://github.com/tukaani-project/xz/security/advisories/GHSA-x872-m794-cxhv\nhttps://github.com/tukaani-project/xz/commit/c8c22869e780ff57c96b46939c3d79ff99395f87\nhttps://github.com/tukaani-project/xz/releases/tag/v5.8.3",
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