Description
In MongoDB, insufficient validation of shard key values during document insertion allowed authenticated users to store documents with specially crafted, operator-shaped objects as shard key values in sharded collections. When change stream events for such documents were processed with the updateLookup full document mode, the crafted values were embedded into internal post-image lookup queries without proper sanitization, causing them to be interpreted as query operators rather than literal equality values. This could result in change stream consumers receiving incorrect post-image documents or encountering non-resumable fatal errors.
Affected products
mongodb: mongodb
References1
- jira.mongodb.org/browse/SERVER-131202 Vendor AdvisoryIssue Tracking
Metrics
- CVSS 3.1
-
5.4
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L - CVSS 4.0
-
2.3
LOW
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:L/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:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 28 · as of 3 November 2026
- CWE
- CWE-943
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