Vulnerability · Published Jun 17, 2026 · Assigned by GitHub_M
CVE-2026-45617LiquidJS: ReDoS via Quadratic Backtracking in `strip_html` Filter Regex
High 7.5
In plain English
A high-severity regular-expression denial of service in liquidjs from harttle. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| npm | liquidjs | 10.26.0 | GHSA-r7g9-xpmj-5fcq |
Affected products (as reported)
Weakness: CWE-1333 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/harttle/liquidjs/security/advisories/GHSA-r7g9-xpmj-5fcq x_refsource_CONFIRM
- https://github.com/harttle/liquidjs/commit/3616a744b9abeb425c217b340a2397d46176afb8 x_refsource_MISC
- https://github.com/harttle/liquidjs/releases/tag/v10.26.0 x_refsource_MISC