Prototype Pollution in Automattic Mongoose
CVE-2026-73562
Mongoose is a MongoDB object modeling tool designed to work in an asynchronous environment. Prior to 6.13.10, 7.8.10, 8.24.1, and 9.7.2, passing a user-controlled update such as MyModel.updateOne(filter, req.body) can exploit Mongoose update casting with a __proto__.x dotted path under $set. Schema.prototype.path and Schema.prototype._getPathType can treat inherited properties of schema.paths and schema.nested as schema types, allowing the casting process to set $fullPath and $parentSchemaDocArray on Object.prototype before throwing. This prototype pollution makes those properties visible on newly created objects and can cause application integrity and availability impacts. This issue is fixed in versions 6.13.10, 7.8.10, 8.24.1, and 9.7.2.
Vulnerability class: Prototype Pollution
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L.
Affected products
- Automattic Mongoose — versions < 6.13.10, >= 7.0.0, < 7.8.10, >= 8.0.0, < 8.24.1
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-73562?
- CVE-2026-73562 is a medium-severity vulnerability in Automattic Mongoose, classified under Improperly Controlled Modification of Object Prototype Attributes (Prototype Pollution). CVSS score: 6.5/10. Published 2026-08-13.
- How severe is CVE-2026-73562?
- Medium severity. CVSS v3 base score is 6.5 out of 10.