Use After Free in Ffmpeg

CVE-2020-21688

A heap-use-after-free in the av_freep function in libavutil/mem.c of FFmpeg 4.2 allows attackers to execute arbitrary code.

Vulnerability class: Use-After-Free

EPSS: 0.017 (75.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Affected products

Ffmpeg — versions 4.2
Debian Debian_linux — versions 11.0
N/a — versions n/a

Weakness classification (CWE)

CWE-416 — Use After Free

Public proof-of-concept exploits

References

cve@mitre.org (Exploit, Patch, x_refsource_MISC, Issue Tracking, Vendor Advisory)
cve@mitre.org (vendor-advisory, Third Party Advisory, x_refsource_DEBIAN)

Frequently asked questions

What is CVE-2020-21688?: CVE-2020-21688 is a high-severity vulnerability in Ffmpeg, classified under Use After Free. CVSS score: 8.8/10. Published 2021-08-10.
How severe is CVE-2020-21688?: High severity. CVSS v3 base score is 8.8 out of 10.
Is CVE-2020-21688 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.