CVE-2026-34166 LiquidJS has a Memory Limit Bypass via Quadratic Amplification in `replace` Filter
Attackers can bypass memory limits in LiquidJS via quadratic amplification in the replace filter, causing out-of-memory conditions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-34166?
CVE-2026-34166 is a low-severity denial of service vulnerability in harttle liquidjs, published on 8 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
LiquidJS is a Shopify / GitHub Pages compatible template engine in pure JavaScript. Prior to 10.25.3, the replace filter in LiquidJS incorrectly accounts for memory usage when the memoryLimit option is enabled. It charges str.length + pattern.length + replacement.length bytes to the memory limiter, but the actual output from str.split(pattern).join(replacement) can be quadratically larger when the pattern occurs many times in the input string. This allows an attacker who controls template content to bypass the memoryLimit DoS protection with approximately 2,500x amplification, potentially causing out-of-memory conditions. This vulnerability is fixed in 10.25.3.
Weakness: CWE-400
Which versions are affected by CVE-2026-34166?
2 open source packages ship an affected version, including liquidjs. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
liquidjs npm | All versions | 10.25.3 |
liquidjs npm | All versions | 10.25.3 |
Products include Liquidjs Liquidjs.
How do I fix CVE-2026-34166?
Upgrade liquidjs to 10.25.3 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-34166 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34166 exists.
Other vulnerabilities in harttle liquidjs
- CVE-2026-30952 liquidjs has a path traversal fallback vulnerability
- CVE-2026-35525 LiquidJS has a root restriction bypass for partial and layout loading through symlinked templates
- CVE-2026-41311 LiquidJS is vulnerable to Denial of Service via circular block reference in layout
- CVE-2026-33285 LiquidJS: memoryLimit Bypass through Negative Range Values Leads to Process Crash
- CVE-2026-33287 LiquidJS has Exponential Memory Amplification through its replace_first Filter $& Pattern
Sources
Also known as GHSA-mmg9-6m6j-jqqx, MINI-mr79-63h7-2r8j, MINI-vr73-v232-qff5.