CVE-2021-27291
python-pygments: ReDoS in multiple lexers
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
1Exploited in Wild
-Decision
Descriptions
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.
En pygments versión 1.1+, corregido en 2.7.4, los lexers usados para analizar unos lenguajes de programación dependen en gran medida en expresiones regulares. Algunas de las expresiones regulares presentan una complejidad exponencial o cúbica en el peor de los casos y son vulnerables a ReDoS. Al diseñar una entrada maliciosa, un atacante puede causar una denegación de servicio
A denial of service attack was discovered against pygments. Some of the regular expressions used to tokenise source code for highlighting have exponential complexity. A specially crafted input file could cause pygments to take effectively infinite time to parse, consuming CPU resources and denying access to the service.
CVSS Scores
SSVC
- Decision:-
Timeline
- 2021-02-16 CVE Reserved
- 2021-03-17 CVE Published
- 2024-01-24 EPSS Updated
- 2024-08-03 CVE Updated
- 2024-08-03 First Exploit
- ---------- Exploited in Wild
- ---------- KEV Due Date
CWE
- CWE-400: Uncontrolled Resource Consumption
- CWE-1333: Inefficient Regular Expression Complexity
CAPEC
References (11)
| URL | Tag | Source |
|---|---|---|
| https://lists.debian.org/debian-lts-announce/2021/03/msg00024.html | Mailing List |
|
| https://lists.debian.org/debian-lts-announce/2021/05/msg00003.html | Mailing List |
|
| https://lists.debian.org/debian-lts-announce/2021/05/msg00006.html | Mailing List |
|
| URL | Date | SRC |
|---|---|---|
| https://gist.github.com/b-c-ds/b1a2cc0c68a35c57188575eb496de5ce | 2024-08-03 |
| URL | Date | SRC |
|---|---|---|
| https://github.com/pygments/pygments/commit/2e7e8c4a7b318f4032493773732754e418279a14 | 2023-11-07 |
Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Pygments Search vendor "Pygments" | Pygments Search vendor "Pygments" for product "Pygments" | >= 1.1 < 2.7.4 Search vendor "Pygments" for product "Pygments" and version " >= 1.1 < 2.7.4" | - |
Affected
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| Debian Search vendor "Debian" | Debian Linux Search vendor "Debian" for product "Debian Linux" | 9.0 Search vendor "Debian" for product "Debian Linux" and version "9.0" | - |
Affected
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| Debian Search vendor "Debian" | Debian Linux Search vendor "Debian" for product "Debian Linux" | 10.0 Search vendor "Debian" for product "Debian Linux" and version "10.0" | - |
Affected
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| Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 32 Search vendor "Fedoraproject" for product "Fedora" and version "32" | - |
Affected
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| Fedoraproject Search vendor "Fedoraproject" | Fedora Search vendor "Fedoraproject" for product "Fedora" | 33 Search vendor "Fedoraproject" for product "Fedora" and version "33" | - |
Affected
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