CVE-2026-33994

Published: Mar 27, 2026 Last Modified: Mar 27, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 6,3
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Confidentiality: N/A
Integrity: N/A
Availability: N/A

Description

AI Translation Available

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.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0005
Percentile
0,1th
Updated

EPSS Score Trend (Last 2 Days)

1321

Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

Incomplete
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Availability
Potential Impacts:
Read Application Data Modify Application Data Dos: Crash, Exit, Or Restart
Applicable Platforms
Languages: JavaScript
View CWE Details
https://github.com/locutusjs/locutus/commit/345a6211e1e6f939f96a7090bfeff642c9f…
https://github.com/locutusjs/locutus/pull/597
https://github.com/locutusjs/locutus/releases/tag/v3.0.25
https://github.com/locutusjs/locutus/security/advisories/GHSA-vc8f-x9pp-wf5p