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TI-2025-22376 Aliases CVE-2025-31115

XZ has a heap-use-after-free bug in threaded .xz decoder

Priority LOW 39CWE-366Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 2 fixed, 1 without a fix

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

XZ Utils provide a general-purpose data-compression library plus command-line tools. In XZ Utils 5.3.3alpha to 5.8.0, the multithreaded .xz decoder in liblzma has a bug where invalid input can at least result in a crash. The effects include heap use after free and writing to an address based on the null pointer plus an offset. Applications and libraries that use the lzma_stream_decoder_mt function are affected. The bug has been fixed in XZ Utils 5.8.1, and the fix has been committed to the v5.4, v5.6, v5.8, and master branches in the xz Git repository. No new release packages will be made from the old stable branches, but a standalone patch is available that applies to all affected releases.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00675 52nd percentileScored 2026-11-07
Fix Partial xz (tukaani-project): 5.8.1Red Hat: 1 advisoryRed Hat: 2 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
tukaani-projectxz5.3.3alpha to before 5.8.15.8.1Patch availableCNA
  • xz Vendortukaani-project Affected 5.3.3alpha to before 5.8.1 Fixed in 5.8.1 Patch available CNA

Remediation

  • Fix · CNA xz (tukaani-project) Fixed in 5.8.1

Red Hat 1 advisory

  • RHSA-2025:7524 Released 2025-05-13 · Red Hat rating Important
    xz security update
    • Red Hat Enterprise Linux AppStream (v. 10) xz-devel-1:5.6.2-4.el10_0, xz-lzma-compat-1:5.6.2-4.el10_0
    • Red Hat Enterprise Linux BaseOS (v. 10) xz-1:5.6.2-4.el10_0, xz-libs-1:5.6.2-4.el10_0

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2025:7524
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2025:7524
Not affected: 4 products
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat OpenShift Container Platform 4

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-31115
  2. 2026-10-06 EPSS moved to the 50th–90th percentile

References

Other 3

  • TI-2024-31891 XZ Utils on Microsoft Windows platform are vulnerable to argument injection CVSS 4.0MEDIUM 6.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences