league/commonmark versions before 2.6.0 contain polynomial time complexity vulnerabilities in Markdown parsing that allow attackers to cause denial of service. Attackers can submit carefully crafted Markdown inputs designed to trigger worst-case performance, and sending multiple requests in parallel exhausts CPU resources and PHP-FPM processes.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact None

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Exploitation none

Automatable yes

Technical Impact partial

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
thephpleague commonmark unaffected
Version Status Constraints
0 affected < 2.6.0
2.6.0 unaffected —

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Project Subscriptions

Vendors Products
Thephpleague Subscribe
Commonmark Subscribe
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/thephpleague/commonmark/security/advisories/GHSA-c2pc-g5qf-rfrf cve-icon cve-icon
https://www.vulncheck.com/advisories/league-commonmark-before-2.6.0-denial-of-service-via-quadratic-complexity cve-icon cve-icon
History

Wed, 09 Sep 2026 15:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 09 Sep 2026 13:45:00 +0000

Type Values Removed Values Added
Description league/commonmark versions before 2.6.0 contain polynomial time complexity vulnerabilities in Markdown parsing that allow attackers to cause denial of service. Attackers can submit carefully crafted Markdown inputs designed to trigger worst-case performance, and sending multiple requests in parallel exhausts CPU resources and PHP-FPM processes.
Title league/commonmark before 2.6.0 Denial of Service via Quadratic Complexity
First Time appeared Thephpleague
Thephpleague commonmark
Weaknesses CWE-407
CPEs cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:*
Vendors & Products Thephpleague
Thephpleague commonmark
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-09-09T14:54:53.318Z

Reserved: 2026-08-16T13:02:14.691Z

Link: CVE-2024-58382

cve-icon Vulnrichment

Updated: 2026-09-09T14:54:42.643Z

cve-icon NVD

Status : Received

Published: 2026-09-09T14:17:10.327

Modified: 2026-09-09T15:17:05.760

Link: CVE-2024-58382

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-09-09T14:45:05Z

Weaknesses