CVE-2021-27291 Information

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.

CVSS Vector

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

Reference

https://gist.github.com/b-c-ds/b1a2cc0c68a35c57188575eb496de5ce https://github.com/pygments/pygments/commit/2e7e8c4a7b318f4032493773732754e418279a14 https://lists.debian.org/debian-lts-announce/2021/03/msg00024.html https://www.debian.org/security/2021/dsa-4878 https://www.debian.org/security/2021/dsa-4889 https://lists.debian.org/debian-lts-announce/2021/05/msg00003.html https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WSLD67LFGXOX2K5YNESSWAS4AGZIJTUQ/ https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GSJRFHALQ7E3UV4FFMFU2YQ6LUDHAI55/ https://lists.debian.org/debian-lts-announce/2021/05/msg00006.html

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

7.5