FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder… (CVE-2026-70629)
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder (libavcodec/rscc.c) that allows attackers to disclose heap memory contents by supplying a crafted video file with a compressed tile that decompresses fewer bytes than the declared tile geometry requires. When rscc_decode_frame() calls av_image_copy_plane() without validating the decompressed byte count against the tile dimensions, the unwritten suffix of the persistent intermediate buffer ctx->inflated_buf is copied into the decoded frame, potentially exposing data from prior heap allocations or previous decoded frames in persistent decoding services.
AI Analysis
Technical Summary
CVE-2026-70629 is an uninitialized heap memory read vulnerability in FFmpeg's native RSCC decoder (libavcodec/rscc.c) affecting versions >=3.0 and <9.0. The issue occurs when rscc_decode_frame() calls av_image_copy_plane() without verifying that the decompressed byte count matches the declared tile geometry. If a crafted video file contains a compressed tile decompressing fewer bytes than declared, the unwritten suffix of the persistent intermediate buffer ctx->inflated_buf is copied into the decoded frame. This can lead to disclosure of heap memory contents from prior allocations or previous decoded frames in persistent decoding services.
Potential Impact
An attacker can cause disclosure of heap memory contents by supplying a specially crafted video file to the vulnerable FFmpeg versions. This may expose sensitive data from prior heap allocations or previous decoded frames. The vulnerability does not affect integrity or availability but has a medium severity impact on confidentiality.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Users should monitor vendor advisories for updates and avoid processing untrusted RSCC-encoded video files until a fix is available.
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder… (CVE-2026-70629)
Description
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native RSCC decoder (libavcodec/rscc.c) that allows attackers to disclose heap memory contents by supplying a crafted video file with a compressed tile that decompresses fewer bytes than the declared tile geometry requires. When rscc_decode_frame() calls av_image_copy_plane() without validating the decompressed byte count against the tile dimensions, the unwritten suffix of the persistent intermediate buffer ctx->inflated_buf is copied into the decoded frame, potentially exposing data from prior heap allocations or previous decoded frames in persistent decoding services.
CVSS v3.1
Score 5.5medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-70629 is an uninitialized heap memory read vulnerability in FFmpeg's native RSCC decoder (libavcodec/rscc.c) affecting versions >=3.0 and <9.0. The issue occurs when rscc_decode_frame() calls av_image_copy_plane() without verifying that the decompressed byte count matches the declared tile geometry. If a crafted video file contains a compressed tile decompressing fewer bytes than declared, the unwritten suffix of the persistent intermediate buffer ctx->inflated_buf is copied into the decoded frame. This can lead to disclosure of heap memory contents from prior allocations or previous decoded frames in persistent decoding services.
Potential Impact
An attacker can cause disclosure of heap memory contents by supplying a specially crafted video file to the vulnerable FFmpeg versions. This may expose sensitive data from prior heap allocations or previous decoded frames. The vulnerability does not affect integrity or availability but has a medium severity impact on confidentiality.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Users should monitor vendor advisories for updates and avoid processing untrusted RSCC-encoded video files until a fix is available.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-824f-v6qw-342h
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-70629"]
- Ecosystems
- []
- Database Specific Severity
- MODERATE
- Cvss Version
- 3.1
Threat ID: 6a75739bbf8831d539d91c27
Added to database: 08/07/2026, 05:56:43 UTC
Last enriched: 08/07/2026, 09:00:32 UTC
Last updated: 08/08/2026, 00:41:15 UTC
Views: 2
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