CVE-2026-105830

HIGH

league/commonmark from 2.0.0 before 2.10.2 contains a quadratic-time denial of service vulnerability in the GitHub Flavored Markdown Table extension's TableStartParser::tryStart() block-start scan. Unauthenticated attackers can submit a large paragraph of pipe-free lines not starting with letters, forcing repeated full-buffer strpos scans that exhaust PHP worker CPU.

CVSS v3.1 Score

7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Published: 10/8/2026Modified: 10/8/2026

Related Intelligence (0)

No articles currently reference this CVE.

References (3)

https://github.com/thephpleague/commonmark/security/advisories/GHSA-3q6v-r5mr-hxv8https://www.vulncheck.com/advisories/league-commonmark-2.0.0-before-2.10.2-quadratic-dos-via-tablestartparserhttps://github.com/thephpleague/commonmark/security/advisories/GHSA-3q6v-r5mr-hxv8