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TI-2026-47027 Aliases CVE-2026-66038GHSA-8mx4-8xfc-qr43

FFmpeg LCL/ZLIB Video Decoder Information Disclosure via lcldec.c

Priority LOW 31CWE-908Published · Updated

Key facts

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

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

Summary

FFmpeg through 8.1.2, fixed in commit 8670835, contains an information disclosure vulnerability in the LCL/ZLIB video decoder that allows attackers to expose uninitialized heap memory by supplying a valid zlib stream that inflates to fewer bytes than the expected frame size. The zlib_decomp() function in lcldec.c treats short decompression as non-fatal and continues to the RGB24 conversion path, which copies a full frame's worth of rows from the allocation buffer using original frame dimensions, causing uninitialized heap contents including pointer-derived allocator bytes to be copied into the attacker-observable AVFrame output and potentially defeating ASLR in long-lived media processing services.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00242 15th percentileScored 2026-11-07
Fix Partial Red Hat: 1 advisoryRed Hat: 1 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
FFmpegFFmpegup to 8.1.2—Patch availableCNA
  • FFmpeg VendorFFmpeg Affected up to 8.1.2 Fixed in — Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:*up to 8.1.2VulnerableFFmpeg
  • cpe:2.3:a:ffmpeg:ffmpeg:*:*:*:*:*:*:*:* Versions up to 8.1.2 Vulnerable ·FFmpeg

Remediation

Red Hat 1 advisory

  • RHSA-2026:73987 Released 2026-09-30 · Red Hat rating Critical
    RHOAI 3.3.7 - Red Hat OpenShift AI
    • Red Hat OpenShift AI 3.3 registry.redhat.io/rhoai/odh-built-in-detector-rhel9, registry.redhat.io/rhoai/odh-dashboard-rhel9, registry.redhat.io/rhoai/odh-data-science-pipelines-argo-argoexec-rhel9 +47

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux AI (RHEL AI) 3AffectedNo fix yet
Red Hat OpenShift AI 3.3Fixed RHSA-2026:73987
Not affected: 1 product
  • Red Hat OpenShift AI 3.3

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-66038
  2. 2026-10-03 Alias added: GHSA-8mx4-8xfc-qr43
  3. 2026-10-07 Fix available: RHSA-2026:73987 · Red Hat

References

Patch 2

  • TI-2025-19015 FFmpeg git-master before commit d5873b was discovered to contain a memory leak in the component libavutil/iamf.c. CVSS 3.1HIGH 8.8
  • TI-2024-21238 FFmpeg 7.0 contains a heap-buffer-overflow at libavfilter/vf_tiltandshift.c:189:5 in copy_column. CVSS 3.1HIGH 8.4
  • TI-2023-06050 Ffmpeg: null pointer dereference in ffmpeg hls parsing CVSS 3.1HIGH 7.5
  • TI-2023-28420 Buffer Overflow vulnerability in Ffmpeg v.N113007-g8d24a28d06 allows a local attacker to… CVSS 3.1HIGH 8.0
  • TI-2023-27357 FFmpeg v.n6.1-3-g466799d4f5 allows a heap-based buffer overflow via the… CVSS 3.1HIGH 8.0
  • TI-2023-27044 Buffer Overflow vulnerability in FFmpeg version n6.1-3-g466799d4f5, allows a local… CVSS 3.1HIGH 8.0
See all 514 →

Sources

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