CVE-2023-22486

cmark-gfm Quadratic complexity bug in handle_close_bracket may lead to a denial of service

HIGH
7.5
CVSS Score
Published: January 24, 2023 at 02:30 AM UTC
Updated: June 17, 2026 at 05:35 AM UTC
1 product affected across 1 vendorCmark Gfm

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Severity
HIGH7.5
Exploit prediction
EPSS 1%
SSVC
PoC

Description

cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. Versions prior to 0.29.0.gfm.7 contain a polynomial time complexity issue in handle_close_bracket that may lead to unbounded resource exhaustion and subsequent denial of service. This vulnerability has been patched in 0.29.0.gfm.7.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Cmark Gfm· GitHubgithub-action
95%
v < 0.29.0.gfm.7
Affected range stops below 0.29.0.gfm.7, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (1)

SSVC — Action Prioritization

SSVCPoCNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-400CWE-407

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