CVE-2026-42334
HIGHCVE-2026-42334 is a high-severity (CVSS 7.5) vulnerability in mongoose. O3 Security confirms whether CVE-2026-42334 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Mongoose: Improper Sanitization of $nor in sanitizeFilter May Allow NoSQL Injection
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, a proxy for how much of the ecosystem is exposed.
mongoosenpmDescription
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 Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | mongoose | all versions | 6.13.9 |
| 📦npm | mongoose | ≥ 7.0.0&&< 7.8.9 | 7.8.9 |
| 📦npm | mongoose | ≥ 8.0.0&&< 8.22.1 | 8.22.1 |
| 📦npm | mongoose | ≥ 9.0.0&&< 9.1.6 | 9.1.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mongoose. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update mongoose to 6.13.9 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-42334 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-42334 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-42334. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-42334 in your dependencies?
O3 detects CVE-2026-42334 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.