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TI-2023-19072 Aliases CVE-2023-37463

Quadratic complexity bugs may lead to a denial of service

Priority HIGH 66CWE-400Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-400.

Summary

cmark-gfm is an extended version of the C reference implementation of CommonMark, a rationalized version of Markdown syntax with a spec. Three polynomial time complexity issues in cmark-gfm may lead to unbounded resource exhaustion and subsequent denial of service. These vulnerabilities have been patched in 0.29.0.gfm.12.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00696 53rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix Fixed cmark-gfm (github): 0.29.0.gfm.12

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
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
GitHubcmark-gfmbefore 0.29.0.gfm.120.29.0.gfm.12Patch availableCNA
  • cmark-gfm VendorGitHub Affected before 0.29.0.gfm.12 Fixed in 0.29.0.gfm.12 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:github:cmark-gfm:*:*:*:*:*:*:*:*before 0.29.0.gfm.12VulnerableGitHub
  • cpe:2.3:a:github:cmark-gfm:*:*:*:*:*:*:*:* Versions before 0.29.0.gfm.12 Vulnerable ·GitHub

Remediation

  • Fix · CNA cmark-gfm (github) Fixed in 0.29.0.gfm.12

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-37463

References

Exploit 1

Other 1

  • TI-2022-08539 Integer overflow in table parsing extension leads to heap memory corruption CVSS 3.1CRITICAL 9.8
  • TI-2023-11632 Quadratic complexity may lead to a denial of service in cmark-gfm CVSS 3.1HIGH 7.5
  • TI-2023-10324 Quadratic complexity may lead to a denial of service in cmark-gfm CVSS 3.1HIGH 7.5
  • TI-2023-08735 cmark-gfm Quadratic complexity bug in handle_close_bracket may lead to a denial of service CVSS 3.1HIGH 7.5
  • TI-2023-08733 Inefficient Quadratic complexity bug in handle_pointy_brace may lead to a denial of service CVSS 3.1HIGH 7.5
  • TI-2023-08732 cmark-gfm Quadratic complexity bugs may lead to a denial of service CVSS 3.1HIGH 7.5
See all 9 →

Sources

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