CVE-2026-42334: Mongoosejs Mongoose

High severity, CVSS 7.5. EPSS: 0.5% chance of exploitation in the next 30 days.

Mongoose is a MongoDB object modeling tool designed to work in an asynchronous environment. Prior to 6.13.9, 7.8.9, 8.22.1, and 9.1.6, a vulnerability allows bypassing Mongoose’s sanitizeFilter query sanitization mechanism via the $nor operator. When sanitizeFilter is enabled, Mongoose wraps query operators in $eq to neutralize them. However, prior to the fix, $nor was not included in the set of logical operators that are recursively sanitized. Because $nor accepts an array (like $and and $or), and arrays do not trigger hasDollarKeys(), malicious operators such as $ne, $gt, or $regex could be injected inside a $nor clause without being sanitized. This vulnerability is fixed in 6.13.9, 7.8.9, 8.22.1, and 9.1.6.

Affected products

• Mongoosejs Mongoose: before 6.13.9 (fixed in 6.13.9); from 7.0.0, before 7.8.9 (fixed in 7.8.9); from 8.0.0, before 8.22.1 (fixed in 8.22.1); from 9.0.0, before 9.1.6 (fixed in 9.1.6)

Published 2026-05-14. Last modified 2026-06-17.