CVE-2026-4539CWE-1333CWE-400

pygments archetype.py AdlLexer redos

Medium · published March 22, 2026

CVSS v4.0
4.8
EPSS
0%
Percentile
5.5
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
4.8 · MEDIUM
Vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
EPSS
0.00165 · 5.5th percentile
Weaknesses
CWE-1333 · Inefficient Regular Expression Complexity; CWE-400 · Uncontrolled Resource Consumption
Published
2026-03-22T05:35Z
EPSS history
Timeline
  • 22 MAR 05:35Z
    pygments archetype.py AdlLexer redos
    cvelistv5