FFmpeg Heap Out-of-Bounds Write via PNG/APNG eXIf Encoder
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- 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-122 and the CVSS impact.
Summary
FFmpeg through 8.1.2, fixed in commit b506faf, contains a heap out-of-bounds write vulnerability in the native PNG and APNG encoders that allows remote attackers to corrupt heap memory by supplying a crafted PNG image with a malicious eXIf chunk. Attackers can craft an eXIf chunk where multiple IFD entries reference the same large value payload, causing canonical serialization to expand the output far beyond the undersized allocation estimated by add_exif_profile_size(), resulting in png_write_chunk() writing tens of thousands of bytes past the buffer boundary, leading to deterministic heap corruption, process crash, and potentially arbitrary code execution.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Red Hat 1 advisory
- RHSA-2026:73987 Released 2026-09-30 · Red Hat rating CriticalRHOAI 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: Important. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux AI (RHEL AI) 3 | Affected | No fix yet |
| Red Hat OpenShift AI 3.3 | Fixed | RHSA-2026:73987 |
Not affected: 1 product
- Red Hat OpenShift AI 3.3
Timeline
- 2026-10-02 Threatist record created from CVE-2026-66040
- 2026-10-03 Alias added: GHSA-6vcg-882j-82v5
- 2026-10-07 Fix available: RHSA-2026:73987 · Red Hat
References
Patch 2
More Ffmpeg vulnerabilities
- 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
Sources
- CVE-2026-66040 · CVE Program
- CVE-2026-66040 · NVD
- FIRST EPSS
- GHSA-6vcg-882j-82v5 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-66040 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences