CVE WatchJul 15, 2026

CVE-2026-25521

Locutus brings stdlibs of other programming languages to JavaScript for educational purposes. In versions from 2.0.12 to before 2.0.39, a pr

CVSS

8.8

High

EPSS

0.3%

p21

KEV

—

Exploit Today

0-100

Published: Feb 4, 2026 · Last modified: Jul 15, 2026 · CWE-1321 · CWE-915

EPSS · 30d

0.3%EPSS · 30 days0.3%

2026-08-092026-09-05

Technical description

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.

Official references

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