PT-2026-86801 · Thephpleague · Commonmark

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CVE-2026-86435

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Published

2026-09-07

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Updated

2026-09-07

CVSS v3.1

7.5

High

VectorAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
commonmark versions from 1.5.0 before 2.8.4 contain a denial of service vulnerability in the Footnote extension that fails to deduplicate footnote definitions. Attackers can craft documents with duplicate footnote definitions and references to create quadratic output expansion, consuming excessive memory and CPU to exhaust server resources.

Fix

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Weakness Enumeration

Related Identifiers

CVE-2026-86435

Affected Products

Commonmark