Medium severity · published Aug 10, 2021
CVE-2020-21697
A heap-use-after-free in the mpeg_mux_write_packet function in libavformat/mpegenc.c of FFmpeg 4.2 allows to cause a denial of service (DOS) via a crafted avi file
6.5
CVSS
0.9%
EPSS
No
On KEV
Description
A heap-use-after-free in the mpeg_mux_write_packet function in libavformat/mpegenc.c of FFmpeg 4.2 allows to cause a denial of service (DOS) via a crafted avi file.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 60% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
11.0 · source: NVD
FF
Ffmpeg · Ffmpeg
4.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-21697
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-21697
Exploit
https://trac.ffmpeg.org/ticket/8188
Third Party Advisory
https://www.debian.org/security/2021/dsa-4998
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