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CVE-2026-115347

CVE-2026-115347 · Mistune before 3.3.0 Quadratic Denial of Service via parse_link_text

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Mistune before 3.3.0 contains an inefficient algorithmic complexity vulnerability in parse_link_text that allows remote attackers to cause denial of service through unbalanced square brackets. Attackers can submit markdown containing long runs of unmatched brackets to mistune.html(), triggering repeated forward scans that stall worker processes for minutes.

CVSS 8.7 · High · EPSS 0.4% · Fix available

Published
Updated

Stack: system

Affected products and versions

  • mistune

    Versions
    • ≥ 0, < 3.3.0: Affected (semver)
    • 3.3.0: Not affected (semver)

    Update to 3.3.0

  • mistune Debian:12

    Versions
    • 2.0.4-1
    • 2.0.4-2
    • 3.0.2-1
    • 3.0.2-2
    • 3.1.3-1
    • 3.1.4-1
    • 3.3.4-1
    • 3.4.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mistune Debian:13

    Versions
    • 3.1.3-1
    • 3.1.4-1
    • 3.3.4-1
    • 3.4.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mistune Debian:14

    Versions
    • 3.1.3-1
    • 3.1.4-1
    • 3.3.4-1
    • 3.4.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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