Bug 2436950 (CVE-2026-25521)

Summary: CVE-2026-25521 locutus: Locutus is vulnerable to Prototype Pollution
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: urgent Docs Contact:
Priority: urgent    
Version: unspecifiedCC: alcohan, gparvin, jbalunas, jcantril, pahickey, rhaigner, rojacob
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A prototype pollution flaw has been discovered in the Locutus npm library. 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.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2436971, 2436972, 2436973, 2436974    
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Description OSIDB Bzimport 2026-02-04 22:01:58 UTC
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.