CVE-2020-21041

Name: CVE-2020-21041
Creator: NVD / NIST
Published: 2021-05-24T18:15:07.8+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 2.05%

Last modified Jun 17, 2026

CVE-2020-21041 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Buffer Overflow vulnerability exists in FFmpeg 4.1 via apng_do_inverse_blend in libavcodec/pngenc.c, which could let a remote malicious user cause a Denial of Service. EPSS estimates a 2.05% chance of exploitation in the next 30 days.

Description

Buffer Overflow vulnerability exists in FFmpeg 4.1 via apng_do_inverse_blend in libavcodec/pngenc.c, which could let a remote malicious user cause a Denial of Service

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

2.05%

78.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-120

Affected Software

Vendor	Product	Versions
Ffmpeg	Ffmpeg	4.1
Debian	Debian Linux	9.0
Debian	Debian Linux	10.0

References

https://lists.debian.org/debian-lts-announce/2021/08/msg00018.htmlMailing List, Third Party Advisory
https://trac.ffmpeg.org/ticket/7989Exploit, Patch, Vendor Advisory
https://www.debian.org/security/2021/dsa-4990Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/08/msg00018.htmlMailing List, Third Party Advisory
https://trac.ffmpeg.org/ticket/7989Exploit, Patch, Vendor Advisory
https://www.debian.org/security/2021/dsa-4990Third Party Advisory

Timeline

Published: May 24, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-21041?

Buffer Overflow vulnerability exists in FFmpeg 4.1 via apng_do_inverse_blend in libavcodec/pngenc.c, which could let a remote malicious user cause a Denial of Service

How severe is CVE-2020-21041?

CVE-2020-21041 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 2.05% probability of exploitation in the next 30 days.

How do I fix CVE-2020-21041?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-21041?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST