VULNERABILITY INTELLIGENCE

CVE-2021-27291

CVSS score7.5 HIGH
EPSS probability3.91%
CISA KEVNot currently listed
Published2021-03-17
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

Weakness classification

  • nvd@nist.gov: CWE-1333

Primary references