CVE-2026-16266

medium

Description

Versions of the package mongo-object before 3.0.3 are vulnerable to Prototype Pollution via the expandKey() function in util.js. An attacker can modify the JavaScript prototype chain by supplying a crafted property path containing special keys such as __proto__.

References

https://security.snyk.io/vuln/SNYK-JS-MONGOOBJECT-13816714

https://github.com/longshotlabs/mongo-object/issues/27

https://github.com/longshotlabs/mongo-object/commit/638314107d8b397e5453c28e41729522b3e8d67c

https://github.com/longshotlabs/mongo-object/blob/4f7a570f2a2fcfa9417b7870d5f859e9574ec73c/src/util.ts%23L251

Details

Source: Mitre, NVD

Published: 2026-07-21

Updated: 2026-07-21

Risk Information

CVSS v2

Base Score: 2.6

Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:P/A:N

Severity: Low

CVSS v3

Base Score: 4

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N

Severity: Medium

CVSS v4

Base Score: 6.3

Vector: 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

Severity: Medium

EPSS

EPSS: 0.00247