Locutus

Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. Starting in version 2.0.39 and prior to version 3.0.25, a prototype pollution vulnerability exists in the `parse_str` function of the npm package locutus. An attacker can pollute `Object.prototype` by overriding `RegExp.prototype.test` and then passing a crafted query string to `parse_str`, bypassing the prototype pollution guard. This vulnerability stems from an incomplete fix for CVE-2026-25521. The CVE-2026-25521 patch replaced the `String.prototype.includes()`-based guard with a `RegExp.prototype.test()`-based guard. However, `RegExp.prototype.test` is itself a writable prototype method that can be overridden, making the new guard bypassable in the same way as the original — trading one hijackable built-in for another. Version 3.0.25 contains an updated fix.

Published: 2026-03-27T22:15:47.131Z
Updated: 2026-04-01T13:45:55.451Z

Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. Prior to version 3.0.25, the `unserialize()` function in `locutus/php/var/unserialize` assigns deserialized keys to plain objects via bracket notation without filtering the `__proto__` key. When a PHP serialized payload contains `__proto__` as an array or object key, JavaScript's `__proto__` setter is invoked, replacing the deserialized object's prototype with attacker-controlled content. This enables property injection, for...in propagation of injected properties, and denial of service via built-in method override. This is distinct from the previously reported prototype pollution in `parse_str` (GHSA-f98m-q3hr-p5wq, GHSA-rxrv-835q-v5mh) — `unserialize` is a different function with no mitigation applied. Version 3.0.25 patches the issue.

Published: 2026-03-27T22:14:03.495Z
Updated: 2026-03-30T15:45:18.660Z

Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. Prior to 3.0.14, the create_function(args, code) function passes both parameters directly to the Function constructor without any sanitization, allowing arbitrary code execution. This is distinct from CVE-2026-29091 which was call_user_func_array using eval() in v2.x. This finding affects create_function using new Function() in v3.x. This vulnerability is fixed in 3.0.14.

Published: 2026-03-12T21:24:51.730Z
Updated: 2026-07-15T01:08:07.107Z

Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. Prior to version 3.0.0, a remote code execution (RCE) flaw was discovered in the locutus project, specifically within the call_user_func_array function implementation. The vulnerability allows an attacker to inject arbitrary JavaScript code into the application's runtime environment. This issue stems from an insecure implementation of the call_user_func_array function (and its wrapper call_user_func), which fails to properly validate all components of a callback array before passing them to eval(). This issue has been patched in version 3.0.0.

Published: 2026-03-06T17:48:10.442Z
Updated: 2026-07-15T01:10:38.893Z

Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. In versions from 2.0.12 to before 2.0.39, a prototype pollution vulnerability exists in locutus. Despite a previous fix that attempted to mitigate prototype pollution by checking whether user input contained a forbidden key, it is still possible to pollute Object.prototype via a crafted input using String.prototype. This issue has been patched in version 2.0.39.

Published: 2026-02-04T21:20:32.643Z
Updated: 2026-07-15T02:49:16.910Z