---
cve: "CVE-2026-33994"
severity: "MEDIUM"
cvss: 6.3
epss: "56%"
vendor: "locutusjs"
kev: false
exploited: false
published: "2026-03-27 22:15:47"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-07T06:42:58+02:00"
---

# CVE-2026-33994

> 6.3 MEDIUM · 🧪 PoC

## Beschreibung

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.

## CVSS-Vektor

```
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- 0d2402bdb92f9c59918114af9c8ba628f22e9152 (Commit)
- 345a6211e1e6f939f96a7090bfeff642c9fcf9e4 (Commit)

## Referenzen

- <https://github.com/locutusjs/locutus/security/advisories/GHSA-vc8f-x9pp-wf5p>
- <https://github.com/locutusjs/locutus/pull/597>
- <https://github.com/locutusjs/locutus/commit/345a6211e1e6f939f96a7090bfeff642c9fcf9e4>
- <https://github.com/locutusjs/locutus/releases/tag/v3.0.25>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-33994) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_