CVE-2021-3566

Description

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).

Category

5.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.10%
Third-Party Advisory github.com Third-Party Advisory debian.org
Affected: n/a ffmpeg
Published at:
Updated at:

References

Link Tags
https://github.com/FFmpeg/FFmpeg/commit/3bce9e9b3ea35c54bacccc793d7da99ea5157532#diff-74f6b92a0541378ad15de9c29c0a2b0c69881ad9ffc71abe568b88b535e00a7f third party advisory patch
https://lists.debian.org/debian-lts-announce/2021/08/msg00018.html third party advisory mailing list

Frequently Asked Questions

What is the severity of CVE-2021-3566?
CVE-2021-3566 has been scored as a medium severity vulnerability.
How to fix CVE-2021-3566?
To fix CVE-2021-3566, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-3566 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-3566 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-3566?
CVE-2021-3566 affects n/a ffmpeg.
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