Cyber Resilience

CVE-2021-27291

HighPublic PoC

Published: 17 March 2021

Published
17 March 2021
Modified
21 November 2024
KEV Added
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Patch
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CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0340 87.7th percentile
Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-27291 is a high-severity Inefficient Regular Expression Complexity (CWE-1333) vulnerability in Debian Debian Linux. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 12.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

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…

more

can cause a denial of service.

CWE(s)
CWE-1333

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

pygments
pygments
1.1 — 2.7.4
debian
debian linux
10.0, 9.0
fedoraproject
fedora
32, 33

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References