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CVE-2026-4539 (GCVE-0-2026-4539)

Vulnerability from cvelistv5 – Published: 2026-03-22 05:35 – Updated: 2026-03-23 16:08
VLAI
Title
pygments archetype.py AdlLexer redos
Summary
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.
Severity
4.8 (Medium)
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
3.3 (Low)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R
3.3 (Low)
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:X/RC:R
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-23 16:08 UTC
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
  • CWE-400 - Resource Consumption
Assigner
References
URL Tags
https://vuldb.com/?id.352327 vdb-entrytechnical-description
https://vuldb.com/?ctiid.352327 signaturepermissions-required
https://vuldb.com/?submit.774685 third-party-advisory
https://github.com/pygments/pygments/issues/3058 exploitissue-tracking
https://github.com/pygments/pygments/ product
Impacted products
Vendor Product Version CPE status
n/a pygments Affected: 2.19.0
Affected: 2.19.1
Affected: 2.19.2
Credits
ybdesire (VulDB User)
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.