TI-2023-10324 Aliases CVE-2023-24824

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

HIGH 72CWE-400Published 2023-03-31 · Updated 2025-02-11

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: Partial Red Hat: 1 fixed, 1 without a fix

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

Summary

cmark-gfm is GitHub's fork of cmark, a CommonMark parsing and rendering library and program in C. A polynomial time complexity issue in cmark-gfm may lead to unbounded resource exhaustion and subsequent denial of service. This CVE covers quadratic complexity issues when parsing text which leads with either large numbers of `>` or `-` characters. This issue has been addressed in version 0.29.0.gfm.10. Users are advised to upgrade. Users unable to upgrade should validate that their input comes from trusted sources.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.01036 64th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix Partial cmark-gfm (github): 0.29.0.gfm.10Red Hat: 1 advisoryRed Hat: 1 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
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

Vendor	Product	Affected versions	Fixed in	Status	Source
GitHub	cmark-gfm	before 0.29.0.gfm.10	0.29.0.gfm.10	Patch available	CNA

cmark-gfm VendorGitHub Affected before 0.29.0.gfm.10 Fixed in 0.29.0.gfm.10 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:github:cmark-gfm::::::::	before 0.29.0.gfm.10.	Vulnerable	GitHub

cpe:2.3:a:github:cmark-gfm:*:*:*:*:*:*:*:* Versions before 0.29.0.gfm.10. Vulnerable ·GitHub

Remediation

Fix · CNA cmark-gfm (github) Fixed in 0.29.0.gfm.10

Red Hat 1 advisory

RHSA-2025:8427 Released 2025-06-03 · Red Hat rating Moderate
pandoc security update
- Red Hat Enterprise Linux CRB (v. 8) pandoc-2.0.6-7.el8_10, pandoc-common-2.0.6-7.el8_10

Vendor assessments

Red Hat

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

Product	Status	Plan or fix
Red Hat 3scale API Management Platform 2	Affected	No fix planned: Will not fix
Red Hat Enterprise Linux CRB (v. 8)	Fixed	RHSA-2025:8427

Timeline

2026-10-02 Threatist record created from CVE-2023-24824

References

Exploit 1

https://github.com/github/cmark-gfm/security/advisories/GHSA-66g8-4hjf-77xh

Patch 1

https://github.com/github/cmark-gfm/commit/2300c1bd2c8226108885bf019655c4159cf26b59

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-2023-19072 Quadratic complexity bugs may lead to a denial of service 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