CVE-2026-9742 Authenticate command with specific mechanism parameter can trigger server crash
Unauthenticated attackers can crash the MongoDB server via the authenticate command when OIDC is enabled, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-9742?
CVE-2026-9742 is a high-severity denial of service vulnerability in Mongodb Mongodb, published on 9 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
When OIDC authentication is enabled in configuration, clients may set specific values in the "mechanism" parameter of the "authenticate" command that lead to server crash. The authenticate command is accessible to unauthenticated clients, leading to pre-auth denial-of-service in affected product configurations.
Weakness: CWE-1287
Which versions are affected by CVE-2026-9742?
1 open source package ship an affected version, including mongodb. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mongodb Bitnami | From 8.2.0 | 8.2.10, 8.3.3 |
Products include Mongodb Mongodb.
How do I fix CVE-2026-9742?
Upgrade mongodb to a fixed version for your release line: 8.2.10 or 8.3.3.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-9742 being exploited?
There is no known exploitation of CVE-2026-9742 in the wild and no public exploit code.
Other vulnerabilities in Mongodb Mongodb
- CVE-2025-14847 MongoDB and MongoDB Server Improper Handling of Length Parameter Inconsistency
- CVE-2026-82067 Auth bypass in MongoDB Server
- CVE-2026-13072 MongoDB Improper Input Validation in Compute Mode External Data Processing Leading to Memory Corruption
- CVE-2017-15535 Denial of service in n/a
- CVE-2026-18691 Improper Authentication in MongoDB Intra-Cluster Connections Allows Credential Exposure
Sources
Also known as BIT-mongodb-2026-9742, GHSA-qwqf-36v4-65w4, MINI-9r52-qw95-2w2r, MINI-cm8r-8qfv-wm7v, UBUNTU-CVE-2026-9742.