CVE-2026-45617

LiquidJS: ReDoS via Quadratic Backtracking in `strip_html` Filter Regex

Published Jun 17, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. In versions 10.25.7 and below, the built-in strip_html filter uses a regex containing four flawed lazy-quantified alternatives, leading to ReDoS via quadratic backtracking. When the input contains many <script, <style, or <!-- opener tokens without matching closers, the V8 regex engine performs O(N²) backtracking, blocking the Node.js event loop. A single ~350 KB request ('<script'.repeat(50000)) stalls the process for ~10 seconds; cost grows quadratically with input size. The default memoryLimit: Infinity does not bound regex CPU, and even when configured strip_html only charges str.length to the limit — the regex itself runs unbounded. A single unauthenticated request containing crafted untrusted input can cause severe event-loop blocking and CPU amplification that saturates Node.js workers while bypassing memoryLimit protections. This issue has been fixed in version 10.26.0.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-r7g9-xpmj-5fcq LiquidJS Vulnerable to ReDoS via Quadratic Backtracking in `strip_html` Filter Regex
History
Type Values Removed Values Added
First Time appeared Harttle
Harttle liquidjs
Vendors & Products Harttle
Harttle liquidjs
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description LiquidJS is a Shopify/GitHub Pages compatible template engine written in pure JavaScript. In versions 10.25.7 and below, the built-in strip_html filter uses a regex containing four flawed lazy-quantified alternatives, leading to ReDoS via quadratic backtracking. When the input contains many <script, <style, or <!-- opener tokens without matching closers, the V8 regex engine performs O(N²) backtracking, blocking the Node.js event loop. A single ~350 KB request ('<script'.repeat(50000)) stalls the process for ~10 seconds; cost grows quadratically with input size. The default memoryLimit: Infinity does not bound regex CPU, and even when configured strip_html only charges str.length to the limit — the regex itself runs unbounded. A single unauthenticated request containing crafted untrusted input can cause severe event-loop blocking and CPU amplification that saturates Node.js workers while bypassing memoryLimit protections. This issue has been fixed in version 10.26.0.
Title LiquidJS: ReDoS via Quadratic Backtracking in `strip_html` Filter Regex
Weaknesses CWE-1333
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Jun 18, 2026, 3:46 PM
Reserved
May 12, 2026, 8:31 PM
Status
Deferred
Published
Jun 17, 2026, 11:17 PM
Modified
Oct 25, 2026, 11:10 PM