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CVE-2021-3566

MEDIUM severity · CVSS 5.5 · Information disclosure
5.5CVSS MEDIUM

Summary

Prior to ffmpeg version 4.3, the tty demuxer did not have a 'read_probe' function assigned to it. By crafting a legitimate "ffconcat" file that references an image, followed by a file the triggers the tty demuxer, the contents of the second file will be copied into the output file verbatim (as long as the `-vcodec copy` option is passed to ffmpeg).

Impact & exploitability

Attack vectorLocal
Attack complexityLow
Privileges requiredNone
User interactionRequired
Confidentiality impactHigh
Integrity impactNone
Availability impactNone
Exploit probability (EPSS)1%

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://github.com/FFmpeg/FFmpeg/commit/3bce9e9b3ea35c54bacccc793d7da99ea5157532#diff-74f6b92a0541378ad15de9c29c0a2b0c69881ad9ffc71abe568b88b535e00a7f ↗