CVE-2026-86435 (GCVE-0-2026-86435)
Vulnerability from cvelistv5
Published
2026-09-07 12:53
Modified
2026-10-08 15:25
Severity ?
8.7 (High) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • CWE-407 - Inefficient Algorithmic Complexity
Summary
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.
References
Impacted products
Vendor Product Version
thephpleague commonmark Version: 1.5.0   ≤
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