BIT-MONGODB-2026-4148 ExpressionContext use-after-free in classic engine $lookup and $graphLookup aggregation operators

A use-after-free vulnerability can be triggered in sharded clusters by an authenticated user with the read role who issues a specially crafted $lookup or $graphLookup aggregation pipeline...

CVE-2026-4148

A use-after-free vulnerability (CVE-2026-4148) affects MongoDB in sharded clusters, triggered by an authenticated user with read role issuing a specially crafted $lookup or $graphLookup aggregation. The linked OSV entry cites the failure in ExpressionContext within the classic engine as the root ...

CVE-2026-4148 ExpressionContext use-after-free in classic engine $lookup and $graphLookup aggregation operators

A use-after-free vulnerability can be triggered in sharded clusters by an authenticated user with the read role who issues a specially crafted $lookup or $graphLookup aggregation pipeline...

PT-2026-25907

Name of the Vulnerable Software and Affected Versions MongoDB Server affected versions not specified Description A use-after-free issue can occur in sharded clusters when a user with read access submits a specifically designed aggregation pipeline using either the $lookup or $graphLookup operator...