p PatchFirst

CVE-2026-48801

CVE-2026-48801 · linkify-it: Quadratic algorithmic complexity in LinkifyIt#match scan loop

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

linkify-it is a links recognition library with full Unicode support. Prior to 5.0.1, LinkifyIt.prototype.match, the package's primary public API, has O(N²) algorithmic complexity for inputs containing many fuzzy links or emails because the JavaScript-level scan loop re-slices input and re-runs unanchored regex searches on progressively shorter tails. Any service that synchronously renders untrusted Markdown with linkify:true on a request hot path can inherit a worker-process denial of service triggerable by a tens-of-KB request body. This issue is fixed in version 5.0.1.

CVSS 8.7 · High · EPSS 0.4% · Fix available

Published
Updated

Stack: system · node

Affected products and versions

  • linkify-it

    Versions
    • < 5.0.1: Affected

    No fix published

  • linkify-it npm

    Affected ranges
    • SEMVER: < 5.0.1

    Update to 5.0.1

  • node-markdown-it Ubuntu:22.04:LTS

    Versions
    • 10.0.0+dfsg-2
    • 10.0.0+dfsg-3
    • 10.0.0+dfsg-3.1
    • 10.0.0+dfsg-4
    • 10.0.0+dfsg-5
    • 10.0.0+dfsg-6
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • node-markdown-it Ubuntu:24.04:LTS

    Versions
    • 22.2.3+dfsg+~12.2.3-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • node-markdown-it Ubuntu:26.10

    Versions
    • 22.2.3+dfsg+~12.2.3-4
    • 22.2.3+dfsg+~12.2.3-5
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • node-markdown-it Ubuntu:26.04:LTS

    Versions
    • 22.2.3+dfsg+~12.2.3-2
    • 22.2.3+dfsg+~12.2.3-4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

Check your server →