# CVE-2026-9742: Authenticate command with specific mechanism parameter can trigger server crash

> CVE-2026-9742: Authenticate command with specific mechanism parameter can trigger server crash. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-9742
Last updated: 2026-07-23T09:10:00Z

- Published: 2026-06-09 21:57 UTC · Updated: 2026-07-23 09:10 UTC · Assigner: mongodb
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 0.35%, 28th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-1287

## 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.

## Affected vendors and products

- MongoDB: MongoDB Server

## Tracked companies

- [MongoDB Atlas](https://rewindex.com/company/mongodb-atlas.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-9742)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-9742)
- [https://jira.mongodb.org/browse/SERVER-124183](https://jira.mongodb.org/browse/SERVER-124183)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-9742 · Markdown: https://rewindex.com/cve/CVE-2026-9742.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-9742 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:50:57.271Z