CVE-2026-9742

Analyzed Analyzed - Analysis Complete

OIDC Mechanism Parameter Crash Leading to Pre-Auth DoS

Publication date: 2026-06-09

Last updated on: 2026-06-18

Assigner: MongoDB, Inc.

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.

CVSS Scores

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Meta Information

Published

2026-06-09

Last Modified

2026-06-18

Generated

2026-06-30

AI Q&A

2026-06-10

EPSS Evaluated

2026-06-28

NVD

CVE-2026-9742

EUVD

EUVD-2026-35860

Affected Vendors & Products

Vendor	Product	Version / Range
mongodb	mongodb	From 8.2.0 (inc) to 8.2.10 (exc)
mongodb	mongodb	From 8.3.0 (inc) to 8.3.3 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-1287	The product receives input that is expected to be of a certain type, but it does not validate or incorrectly validates that the input is actually of the expected type.

Attack-Flow Graph

Executive Summary

This vulnerability occurs when OpenID Connect (OIDC) authentication is enabled in the configuration of the affected product. Clients can set specific values in the "mechanism" parameter of the "authenticate" command, which can cause the server to crash.

The "authenticate" command is accessible to unauthenticated clients, meaning that anyone can send this command without prior authentication.

As a result, this leads to a denial-of-service (DoS) condition before authentication (pre-auth), disrupting the availability of the server.

Impact Analysis

The primary impact of this vulnerability is a denial-of-service (DoS) attack that can crash the server.

Since the "authenticate" command is accessible without authentication, an attacker can exploit this vulnerability remotely to cause the server to become unavailable.

This can lead to service disruption, affecting availability and potentially causing downtime for users relying on the affected system.

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