CVE-2026-26021

set-in provides the set value of nested associative structure given array of keys. A prototype pollution vulnerability exists in the the npm package set-in (>=2.0.1, < 2.0.5). 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 Array.prototype. This has been fixed in version 2.0.5.

CVSS v3 9.8 CRITICAL

9.8^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 3.9 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/ahdinosaur/set-in/commit/b8e1dabfdbd35c8d604b6324e01d03f280256c3d	Patch
https://github.com/ahdinosaur/set-in/security/advisories/GHSA-2c4m-g7rx-63q7	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:set-in_project:set-in:*:*:*:*:*:*:*:*

History

13 Feb 2026, 21:43

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 9.8
CPE		cpe:2.3:a:set-in_project:set-in::::::::
References	~~() https://github.com/ahdinosaur/set-in/commit/b8e1dabfdbd35c8d604b6324e01d03f280256c3d -~~	() https://github.com/ahdinosaur/set-in/commit/b8e1dabfdbd35c8d604b6324e01d03f280256c3d - Patch
References	~~() https://github.com/ahdinosaur/set-in/security/advisories/GHSA-2c4m-g7rx-63q7 -~~	() https://github.com/ahdinosaur/set-in/security/advisories/GHSA-2c4m-g7rx-63q7 - Exploit, Vendor Advisory
First Time		Set-in Project Set-in Project set-in

11 Feb 2026, 22:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-02-11 22:15

Updated : 2026-02-13 21:43

NVD link : CVE-2026-26021

Mitre link : CVE-2026-26021

CVE.ORG link : CVE-2026-26021

JSON object : View

Products Affected

set-in_project

set-in

CWE

CWE-1321

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

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