CVE-2026-26021
Prototype pollution in set-in
CRITICAL 9.4EPSS 0.6%
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.
- Affected
- ahdinosaur · set-in
- CVSS v4.0 GITHUB
- 9.4 CRITICAL
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS v4.0 GitHub
- 9.4 CRITICAL
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H - CVSS v3.1 NVD
- 9.8 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS
- 0.56% chance of exploitation in the next 30 days, 46th percentile
- Published
- 2026-02-11
- Updated
- 2026-02-12
Proof-of-concept exploits (1)
Security advisories
- ahdinosaur/set-in/security/advisories/GHSA-2c4m-g7rx-63q7
- ahdinosaur/set-in/commit/b8e1dabfdbd35c8d604b6324e01d03f280256c3d