Description
In pygments 1.1+, fixed in 2.7.4, the lexers used to parse programming languages rely heavily on regular expressions. Some of the regular expressions have exponential or cubic worst-case complexity and are vulnerable to ReDoS. By crafting malicious input, an attacker can 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:HWeakness enumeration
Affected software
| Vendor | Product | Versions |
|---|---|---|
| n/a | n/a | n/a |
References
- https://gist.github.com/b-c-ds/b1a2cc0c68a35c57188575eb496de5ceExploit, Third Party Advisory
- https://github.com/pygments/pygments/commit/2e7e8c4a7b318f4032493773732754e418279a14Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/03/msg00024.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/05/msg00003.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/05/msg00006.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GSJRFHALQ7E3UV4FFMFU2YQ6LUDHAI55/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WSLD67LFGXOX2K5YNESSWAS4AGZIJTUQ/
- https://www.debian.org/security/2021/dsa-4878Third Party Advisory
- https://www.debian.org/security/2021/dsa-4889Third Party Advisory
- https://gist.github.com/b-c-ds/b1a2cc0c68a35c57188575eb496de5ceExploit, Third Party Advisory
- https://github.com/pygments/pygments/commit/2e7e8c4a7b318f4032493773732754e418279a14Patch, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/03/msg00024.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/05/msg00003.htmlMailing List, Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2021/05/msg00006.htmlMailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/GSJRFHALQ7E3UV4FFMFU2YQ6LUDHAI55/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WSLD67LFGXOX2K5YNESSWAS4AGZIJTUQ/
- https://www.debian.org/security/2021/dsa-4878Third Party Advisory
- https://www.debian.org/security/2021/dsa-4889Third Party Advisory
Timeline
- Published
- Mar 17, 2021
- Last modified
- Jun 17, 2026
- NVD status
- Modified