CVE-2026-81490: MongoDB Connector for BI Improper Error Handling During Schema Sampling May Cause Loss of SQL Service
A database user able to create a view in a namespace that MongoDB Connector for BI samples can cause the schema-sampling routine to stop functioning by defining a view whose evaluation reliably fails. The sampling logic classifies the resulting server message as transient and, after the configured retries are exhausted, proceeds without a valid result, ending the schema refresh routine. The mongosqld process continues running without a usable schema, so SQL clients are unable to obtain results until an operator removes the view or excludes its namespace from sampling.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Remove
Remove
MongoDB Connector for BI - problematic view in the target namespacefrom your environment.Remove the view that causes schema-sampling evaluation to reliably fail so the mongosqld schema refresh routine can obtain a usable schema.
- Configuration
Exclude the view’s namespace from the schema-sampling routine so mongosqld regains a usable schema.
MongoDB Connector for BI schema sampling namespace sampling scope = exclude the namespace containing the problematic view - Operational
After removing the view or excluding its namespace from sampling, re-run/trigger the schema refresh routine so SQL clients can obtain results again.
Event History
Frequently Asked Questions
Who can exploit this issue?
An attacker needs database-user permissions sufficient to create a view in a namespace that MongoDB Connector for BI samples. No user interaction is required.
What is the operational impact?
The mongosqld process remains running, but schema refresh ends without a usable schema. SQL clients then cannot obtain results, creating a denial-of-service condition for BI Connector SQL access.
How can operators recover if affected?
Remove the view whose evaluation reliably fails, or exclude that view's namespace from schema sampling. Either action prevents the problematic namespace from stopping the schema refresh routine.