Security Advisory
CVE-2026-86433
CVSS 7.5
HIGH
Vulnerability Description
commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Attributes extension where AttributesListener::findTargetAndDirection() performs quadratic-time sibling list scanning. Unauthenticated attackers can submit approximately 32 KB of repeated attribute blocks to cause parsing to take over 5 seconds, exhausting server resources.
Published Date
2026-09-07T13:20:42.733
Data Feed
NIST National Vulnerability Database