CVE-2020-21048

Name: CVE-2020-21048
Creator: NVD / NIST
Published: 2021-09-14T16:15:08.403+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.33%

Last modified Jun 17, 2026

CVE-2020-21048 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. An issue in the dither.c component of libsixel prior to v1.8.4 allows attackers to cause a denial of service (DOS) via a crafted PNG file.. EPSS estimates a 1.33% chance of exploitation in the next 30 days.

Description

An issue in the dither.c component of libsixel prior to v1.8.4 allows attackers to cause a denial of service (DOS) via a crafted PNG file.

Metrics

CVSS 3.1

6.5/10

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

EPSS Probability

1.33%

67.5th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Saitoha	Libsixel	< 1.8.4

References

https://bitbucket.org/netbsd/pkgsrc/commits/6f0c011cbfccdffa635d04c84433b1a02687adadBroken Link
https://github.com/saitoha/libsixel/blob/master/ChangeLogRelease Notes, Third Party Advisory
https://github.com/saitoha/libsixel/commit/cb373ab6614c910407c5e5a93ab935144e62b037Patch, Third Party Advisory
https://github.com/saitoha/libsixel/issues/73Exploit, Issue Tracking, Patch, Third Party Advisory
https://github.com/saitoha/libsixel/releases/tag/v1.8.4Release Notes, Third Party Advisory
https://bitbucket.org/netbsd/pkgsrc/commits/6f0c011cbfccdffa635d04c84433b1a02687adadBroken Link
https://github.com/saitoha/libsixel/blob/master/ChangeLogRelease Notes, Third Party Advisory
https://github.com/saitoha/libsixel/commit/cb373ab6614c910407c5e5a93ab935144e62b037Patch, Third Party Advisory
https://github.com/saitoha/libsixel/issues/73Exploit, Issue Tracking, Patch, Third Party Advisory
https://github.com/saitoha/libsixel/releases/tag/v1.8.4Release Notes, Third Party Advisory

Timeline

Published: Sep 14, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-21048?

An issue in the dither.c component of libsixel prior to v1.8.4 allows attackers to cause a denial of service (DOS) via a crafted PNG file.

How severe is CVE-2020-21048?

CVE-2020-21048 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.33% probability of exploitation in the next 30 days.

How do I fix CVE-2020-21048?

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-2020-21048?

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

Scan your code now

Source: NVD / NIST