CVE-2026-86428
HIGH
NVD
CVSS Score
7.5
Severity
HIGH
Published
Sep 07, 2026
Vendor
unknown
Description
commonmark versions from 1.5.0 before 2.10.0 contain a denial of service vulnerability in the AttributesExtension when processing distinctly-named attributes. Attackers can submit Markdown with numerous distinct attribute names to cause quadratic-time attribute merging and filtering, consuming disproportionate CPU resources and preventing legitimate requests from completing.