high7.5
CVE-2021-27291
Pygments vulnerable to Regular Expression Denial of Service (ReDoS)
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| pip | Pygments | >= 1.1, < 2.7.4 | 2.7.4 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Pygments | Pygments | from 1.1 before 2.7.4 |
| Debian | Debian Linux | Versions 9.0, 10.0 |
| Fedoraproject | Fedora | Versions 32, 33 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- 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://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/
- https://www.debian.org/security/2021/dsa-4878
- https://www.debian.org/security/2021/dsa-4889
- https://github.com/advisories/GHSA-pq64-v7f5-gqh8
- https://nvd.nist.gov/vuln/detail/CVE-2021-27291
- https://github.com/pypa/advisory-database/tree/main/vulns/pygments/PYSEC-2021-141.yaml
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/GSJRFHALQ7E3UV4FFMFU2YQ6LUDHAI55
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WSLD67LFGXOX2K5YNESSWAS4AGZIJTUQ