MEDIUM · 4.0

CVE-2026-16266

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 cr...

Vulnerability 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__.

CVSS Score

4.0

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:L/A:N
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE

Related Weaknesses (CWE)

References

FAQ

What is CVE-2026-16266?

CVE-2026-16266 is a vulnerability with a CVSS score of 4.0 (MEDIUM). 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 cr...

How severe is CVE-2026-16266?

CVE-2026-16266 has been rated MEDIUM with a CVSS base score of 4.0/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-16266?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.