CVE-2026-81520

A network-reachable client that has not yet authenticated can hold a MongoDB Connector for BI authentication session open indefinitely by beginning a SASL-based login exchange and then declining to complete it. Because the negotiation loop had no overall time bound and the read from the client had no deadline, each such session retains a worker, a client connection slot, and its associated backend database connections until the process is restarted. Repeated use of this behavior can consume the configured connection capacity and prevent legitimate users from establishing new sessions.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.mongodb.com/docs/bi-connector/current/release-notes/	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:mongodb:bi_connector:*:*:*:*:*:*:*:*

History

29 Sep 2026, 19:14

Type	Values Removed	Values Added
First Time		Mongodb bi Connector Mongodb
References	~~() https://www.mongodb.com/docs/bi-connector/current/release-notes/ -~~	() https://www.mongodb.com/docs/bi-connector/current/release-notes/ - Vendor Advisory
CPE		cpe:2.3:a:mongodb:bi_connector::::::::

Information

Published : 2026-08-28 22:16

Updated : 2026-09-29 19:14

NVD link : CVE-2026-81520

Mitre link : CVE-2026-81520

CVE.ORG link : CVE-2026-81520

JSON object : View

Products Affected

mongodb

bi_connector

CWE

CWE-1088

Synchronous Access of Remote Resource without Timeout

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