p PatchFirst

CVE-2026-116795

CVE-2026-116795 · RE2JS: Quadratic-time denial of service in re2js lookbehind matching

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

RE2JS is the JavaScript port of RE2, a regular expression engine that provides linear time matching. From 2.2.0 until 2.8.7, enabling LOOKBEHINDS and using repeated matching through matcher().find(), matchAll(), split(), or matcher().replaceAll() can cause quadratic total work. Machine.match restarts lookbehind scanning from offset zero for each requested start position, while Matcher-based APIs request capture slots that prevent the early exit used for captureless matching. Dense matches therefore repeatedly rescan the input, allowing attacker-influenced text to monopolize a single-threaded worker and deny service. This issue is fixed in version 2.8.7.

CVSS 7.5 · High · EPSS 0.5% · Public exploit · Fix available

Published
Updated

Stack: node

Affected products and versions

  • re2js

    Versions
    • >= 2.2.0, < 2.8.7: Affected

    No fix published

  • re2js npm

    Affected ranges
    • SEMVER: ≥ 2.2.0, < 2.8.7

    Update to 2.8.7

Original sources

Check your server →