PatchSiren cyber security CVE debrief
CVE-2026-64833 FFmpeg CVE debrief
CVE-2026-64833 is an out-of-bounds read vulnerability in the S/PDIF muxer of FFmpeg versions 0.7.1 through 8.1.2. The vulnerability allows attackers to access memory beyond buffer boundaries by supplying a crafted DTS stream with a core_size value larger than the actual packet length. This can be exploited during S/PDIF re-muxing to trigger unauthorized memory reads. The vulnerability has a high severity with a CVSS score of 7.1. Developers and administrators using affected FFmpeg versions should be aware of this vulnerability and take steps to mitigate it. The CVE record was published on 2026-07-22T18:17:05.627Z and has not been modified since then.
- Vendor
- FFmpeg
- Product
- Unknown
- CVSS
- HIGH 7.1
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-07-22
- Original CVE updated
- 2026-08-12
- Advisory published
- 2026-07-22
- Advisory updated
- 2026-08-12
Who should care
Developers and administrators using FFmpeg versions 0.7.1 through 8.1.2 should be aware of this high-severity vulnerability and take steps to mitigate it. This includes reviewing system configurations, updating FFmpeg to a patched version, and monitoring for potential exploitation attempts. Security teams and vulnerability management teams should prioritize patching and review compensating controls for exposed systems.
Technical summary
CVE-2026-64833 is an out-of-bounds read vulnerability in the S/PDIF muxer of FFmpeg. The vulnerability allows attackers to access memory beyond buffer boundaries by supplying a crafted DTS stream with a core_size value larger than the actual packet length. This can be exploited by providing a malicious DTS-HD audio stream during S/PDIF re-muxing to trigger unauthorized memory reads beyond the packet buffer. The vulnerability has a high severity with a CVSS score of 7.1.
Defensive priority
High priority should be given to updating FFmpeg to a version that patches this vulnerability and reviewing compensating controls for exposed systems.
Recommended defensive actions
- Update FFmpeg to a version that patches this vulnerability
- Review and monitor FFmpeg usage in your environment
- Implement compensating controls to detect and prevent exploitation
- Review system configurations for S/PDIF re-muxing and DTS-HD audio stream handling
- Monitor for suspicious memory access patterns and potential exploitation attempts
- Track exceptions and retest remediated assets
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
Evidence notes
The CVE record and NVD entry provide details on this vulnerability. However, the exact scope of affected systems and potential attack vectors require further investigation. Affected systems likely include those using FFmpeg versions 0.7.1 through 8.1.2 for S/PDIF re-muxing. Defenders should verify system configurations, review DTS-HD audio stream handling, and monitor for suspicious memory access patterns. Evidence is limited to public CVE and NVD descriptions, so additional verification is necessary.
Sources and references
Verified primary and authoritative sources
-
CVE-2026-64833 CVE Program record
Publisher, destination, and source semantics verified
URL: https://www.cve.org/CVERecord?id=CVE-2026-64833
CVE Program - Official CVE Program record with source-provided CVE metadata.
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CVE-2026-64833 NVD vulnerability detail
Publisher, destination, and source semantics verified
URL: https://nvd.nist.gov/vuln/detail/CVE-2026-64833
NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.
Supplemental references
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Source reference
Unverified legacy reference
URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/6f80e2765492700622596af720534cef33dd31b4
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Source reference
Unverified legacy reference
URL: https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23661
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Source reference
Unverified legacy reference
URL: https://www.vulncheck.com/advisories/ffmpeg-out-of-bounds-read-via-s-pdif-muxer-spdifenc-c
Methodology and review provenance
AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.