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.
Affected products
tukaani: xz
References5
- github.com/tukaani-project/xz/security/advisories/GHSA-x872-m79… Vendor Advisory
- github.com/tukaani-project/xz/commit/c8c22869e780ff57c96b46939c… Patch
- www.openwall.com/lists/oss-security/2026/03/31/13 Mailing ListPatchThird Party Advisory
- github.com/tukaani-project/xz/releases/tag/v5.8.3 ProductRelease Notes
- lists.debian.org/debian-lts-announce/2026/07/msg00034.html
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 4.0
-
1.7
LOW
Score source: CNA
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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 1% percentile: 46 · as of 12 November 2026
- CWE
- CWE-122
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