CVE-2026-4539

LOW

pygments archetype.py AdlLexer redos

Title source: cna
STIX 2.1

Description

A security flaw has been discovered in pygments up to 2.19.2. The impacted element is the function AdlLexer of the file pygments/lexers/archetype.py. The manipulation results in inefficient regular expression complexity. The attack is only possible with local access. The exploit has been released to the public and may be used for attacks. The project was informed of the problem early through an issue report but has not responded yet.

Scores

CVSS v3 3.3
EPSS 0.0001
EPSS Percentile 0.7%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-1333 CWE-400
Status published
Products (4)
n/a/pygments 2.19.0
n/a/pygments 2.19.1
n/a/pygments 2.19.2
pypi/Pygments 0PyPI
Published Mar 22, 2026
Tracked Since Mar 22, 2026