CVE-2026-86432

MEDIUMCVSS 5.3

Description

commonmark versions from 2.0.0 before 2.8.4 contain a denial of service vulnerability in XmlRenderer that emits depth-proportional indentation for every XML tag. Attackers can provide deeply nested Markdown or AST structures to cause quadratic memory consumption and output amplification, exhausting server resources.

Timeline

Published:September 7th, 2026 1:20 PM

Last modified:September 8th, 2026 7:57 PM

CVSS Scoring

CVSS v3: 5.3 (MEDIUM)

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Weaknesses (CWE)

CWE-405

References & Reports

Advisories, patches, and third-party reports

https://github.com/thephpleague/commonmark/security/advisories/GHSA-mj63-m3rc-8ppr
https://www.vulncheck.com/advisories/commonmark-2.0.0-before-2.8.4-denial-of-service-via-xml

Source: NIST NVD · Data may lag official sources by up to one minute