7.1

CVE-2026-66038

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

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.
Daten sind bereitgestellt durch National Vulnerability Database (NVD)
FfmpegFfmpeg Version <= 8.1.2
VulnDex Vulnerability Enrichment
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Zu dieser CVE wurde keine Warnung gefunden.
EPSS Metriken
Typ Quelle Score Percentile
EPSS FIRST.org 0.25% 0.158
CVSS Metriken
Quelle Base Score Exploit Score Impact Score Vector String
NIST 6.5 2.8 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
disclosure@vulncheck.com 7.1 0 0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
disclosure@vulncheck.com 6.5 2.8 3.6
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CWE-908 Use of Uninitialized Resource

The product uses or accesses a resource that has not been initialized.

https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/23626
Patch
Issue Tracking
https://code.ffmpeg.org/FFmpeg/FFmpeg/commit/e7cbfd1c507b57a806a5825b87d609963e862c8c
Patch
https://www.vulncheck.com/advisories/ffmpeg-lcl-zlib-video-decoder-information-disclosure-via-lcldec-c
Third Party Advisory