CVE-2026-70630
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native Screenpresso decoder (libavcodec/screenpresso.c) that allows attackers to recover sensitive memory contents by supplying a crafted SPV1 packet with a valid zlib stream that decompresses fewer bytes than the full frame requires. The screenpresso_decode_frame() function fails to validate the produced byte count before calling av_image_copy_plane() to copy the complete frame dimensions from the persistent ctx->inflated_buf buffer, causing unwritten heap memory from prior allocations or prior frames to be copied into decoded output and potentially exposing sensitive data such as userspace addresses from persistent decoding services.
脆弱性の種類
FFmpeg versions from 3.0 up to, but not including, 9.0 contain an uninitialized heap memory read vulnerability in the native Screenpresso decoder (libavcodec/screenpresso.c) that allows attackers to recover sensitive memory contents by supplying a crafted SPV1 packet with a valid zlib stream that decompresses fewer bytes than the full frame requires. The screenpresso_decode_frame() function fails to validate the produced byte count before calling av_image_copy_plane() to copy the complete frame dimensions from the persistent ctx->inflated_buf buffer, causing unwritten heap memory from prior allocations or prior frames to be copied into decoded output and potentially exposing sensitive data such as userspace addresses from persistent decoding services.
影響を受ける製品
- ffmpeg ffmpeg
参考情報
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/705890061467ad550ecc1dad5eea07f28ccfb43e
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/9a3202a98b2e095b54dd784c3e01a09a676fc3fa
- https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/c22667d0fd7916a33fd3e79685b7246fc48f1a62
- https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23896
- https://www.vulncheck.com/advisories/ffmpeg-uninitialized-heap-memory-read-in-screenpresso-decoder