Description
The `$_internalIndexKey` aggregation expression can be used by any authenticated user to crash a MongoDB server (mongod). The expression fails to handle compound wildcard index specifications, triggering an internal consistency check that aborts the server process. The user must be able to run an aggregation pipeline.
Affected products
mongodb: mongodb
References1
- jira.mongodb.org/browse/SERVER-123081 Vendor AdvisoryIssue Tracking
Metrics
- CVSS 3.1
-
6.5
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H - CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:A/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 35 · as of 14 November 2026
- CWE
- CWE-617
Could this be exploited in your environment?
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