$_internalConvertBucketIndexStats may crash the mongod server when working on no timeseries input
CVE-2026-9748

7.1HIGH

Key Information:

Vendor

Mongodb
Status
Mongodb Server
Vendor
CVE Published:
9 June 2026

What is CVE-2026-9748?

The $_internalConvertBucketIndexStats stage used PauseExecution as a way to signal "skip this document" when an index stats conversion failed. But PauseExecution is not a general purpose skip mechanism, but rather a TeeBuffer-internal signal used solely by $facet to coordinate its sub-pipelines. When this stage is placed before $facet in a pipeline, TeeBuffer receives the unexpected PauseExecution from upstream and hits a hard invariant assertion, crashing mongod.

Affected Version(s)

MongoDB Server 8.3.0 < 8.3.3

MongoDB Server 8.2.0 < 8.2.10

MongoDB Server 8.0.0 < 8.0.10

References

https://jira.mongodb.org/browse/SERVER-123951

CVSS V4

Score:
7.1
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

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