CVE-2026-81518 HIGH

CVE-2026-81518: BI Connector Optional Client Certificate Verification Allows Unauthenticated Connections

Vendor Mongodb
Product BI Connector
Weakness CWE-295
Published August 28, 2026
Last update August 28, 2026

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality
Integrity

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

When mongosqld is configured with a client certificate authority file, the listener requests a client certificate during the TLS handshake but does not require one, so a client that presents no certificate is still accepted. In deployments that rely on client certificates as the sole means of identifying users, a remote party with network access to the listener can therefore establish a session and read the MongoDB data exposed through the connector.

Key dates

02Disclosure timeline

August 28, 2026 CVE published