Vulnerability in Automattic Mongoose
CVE-2026-42334
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.005 (37.7th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 38th percentile — 37.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.005 · change: +0.002
Affected products
- Automattic Mongoose — versions < 6.13.9, >= 7.0.0, <= 7.8.8, >= 8.0.0, <= 8.22.0
- Mongoosejs Mongoose
Weakness classification (CWE)
References
- github.com/Automattic/mongoose/security/advisories/GHSA-wpg9-53fq-2r8h (Mitigation, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-42334?
- CVE-2026-42334 is a high-severity vulnerability in Automattic Mongoose, classified under Improper Neutralization of Special Elements in Output Used by a Downstream Component (Injection). CVSS score: 7.5/10. Published 2026-05-14.
- How severe is CVE-2026-42334?
- High severity. CVSS v3 base score is 7.5 out of 10.