Vulnerabilities > CVE-2021-27291
Attack vector
NETWORK Attack complexity
LOW Privileges required
NONE Confidentiality impact
NONE Integrity impact
NONE Availability impact
HIGH Summary
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.
Vulnerable Configurations
| Part | Description | Count |
|---|---|---|
| Application | 10 | |
| OS | 2 | |
| OS | 2 |
References
- 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.debian.org/debian-lts-announce/2021/05/msg00006.html
- 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/