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TI-2026-83087 Aliases CVE-2026-119602GHSA-xxh6-gw5r-86fm

Uninitialized memory disclosure in libmspack MS-ZIP decompressor

Priority LOW 28CWE-908Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
Present
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Deferred Red Hat: fix deferred

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-908 and the CVSS impact.

Summary

libmspack from 0 through 0.11alpha is affected. The MS-ZIP decompressor does not check back-reference distances in the first block, a weakness classified as CWE-908 (Use of Uninitialized Resource). An attacker can supply a crafted MS-ZIP CAB file so that extraction writes up to 32 KiB of stale heap memory into the extracted output.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

Description from the CNA

libmspack through 0.11alpha contains an uninitialized memory disclosure vulnerability in the MS-ZIP decompressor that allows attackers to leak heap data via unchecked back-reference distances. Attackers can supply a crafted MS-ZIP CAB file whose first block begins with a back-reference, causing cabd->extract() to write up to 32 KiB of stale heap memory into extracted output.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00307 23rd percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred

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
kyzlibmspackup to 0.11alpha—No fix listedCNA
  • libmspack Vendorkyz Affected up to 0.11alpha Fixed in — No fix listed CNA

Remediation

No fixed version is listed for libmspack. Red Hat lists Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 and Red Hat OpenShift Container Platform 5 as affected with no plan available.

Written with Claude Haiku 5.5 from the sources below · 2026-11-02

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred

Timeline

  1. 2026-10-30 Threatist record created from CVE-2026-119602
  2. 2026-10-30 CISA SSVC decision points changed
  3. 2026-10-30 Priority changed: MEDIUM → LOW
  4. 2026-10-30 Alias added: GHSA-xxh6-gw5r-86fm
  5. 2026-10-30 Affected versions changed · Red Hat
  6. 2026-10-30 CVSS score added · Red Hat
  7. 2026-10-31 Affected versions changed · Red Hat
  8. 2026-11-02 Affected versions changed · Red Hat

References

Advisory 1

Other 3

  • TI-2026-74096 Uninitialized pointer free in libmspack KWAJ header handling CVSS 4.0MEDIUM 5.8

Sources

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