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TI-2026-82220 Aliases CVE-2026-118694GHSA-rgrp-3mvm-5g9j

Denial of service in python-markdown2 via unclosed inline links

Priority MEDIUM 44CWE-407Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-407.

Summary

python-markdown2 through 2.5.5 is affected. Its inline link parser, _find_balanced, rescans the rest of the document for each unclosed link destination, which causes quadratic CPU use (CWE-407). A remote attacker without privileges can submit crafted Markdown to exhaust CPU and deny service to the application.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Description from the CNA

python-markdown2 through 2.5.5 contains a denial of service vulnerability that allows remote users to exhaust CPU by submitting Markdown with unclosed inline link destinations. Attackers can submit repeated '[a](' or '![a](' sequences, causing _find_balanced to rescan the remaining document for each link and consume quadratic CPU time.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00453 39th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
trentmpython-markdown2up to 2.5.5—No fix listedCNA
  • python-markdown2 Vendortrentm Affected up to 2.5.5 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for python-markdown2. Red Hat lists Red Hat OpenShift Container Platform 4 as affected, with its plan marked none available.

Written with Claude Haiku 5.5 from the sources below · 2026-10-30

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat OpenShift Container Platform 4AffectedNo fix yet

Timeline

  1. 2026-10-28 Threatist record created from CVE-2026-118694
  2. 2026-10-29 Alias added: GHSA-rgrp-3mvm-5g9j
  3. 2026-10-29 CISA SSVC decision points changed
  4. 2026-10-30 Affected versions changed · Red Hat
  5. 2026-10-30 CVSS score added · Red Hat

References

Patch 1

Other 4

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences