CVE-2026-4148 PUBLISHED

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

Assigner: mongodb
Reserved: 13.03.2026 Published: 17.03.2026 Updated: 17.03.2026

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.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CVSS Score: 8.7

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	None	Availability	High	Availability	None
Privileges Required	Low
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS Score: 8.8

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	Low	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	MongoDB Inc
Product	MongoDB Server
Versions	Default: unaffected affected from 8.2 to 8.2.6 (excl.) affected from 8.0 to 8.0.20 (excl.) affected from 7.0 to 7.0.31 (excl.)

References

https://jira.mongodb.org/browse/SERVER-119319

Problem Types

CWE-416 Use after free CWE