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 crafted property path containing special keys such as __proto__.

CVSS v3 4.0 MEDIUM

4.0^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/longshotlabs/mongo-object/blob/4f7a570f2a2fcfa9417b7870d5f859e9574ec73c/src/util.ts%23L251
https://github.com/longshotlabs/mongo-object/commit/638314107d8b397e5453c28e41729522b3e8d67c
https://github.com/longshotlabs/mongo-object/issues/27
https://security.snyk.io/vuln/SNYK-JS-MONGOOBJECT-13816714
https://github.com/longshotlabs/mongo-object/issues/27

Configurations

No configuration.

History

21 Jul 2026, 16:17

Type	Values Removed	Values Added
References	~~() https://github.com/longshotlabs/mongo-object/issues/27 -~~	() https://github.com/longshotlabs/mongo-object/issues/27 -

21 Jul 2026, 06:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-21 06:16

Updated : 2026-07-21 16:17

NVD link : CVE-2026-16266

Mitre link : CVE-2026-16266

CVE.ORG link : CVE-2026-16266

JSON object : View

Products Affected

No product.

CWE

CWE-1321

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

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