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Status published
Medium
CVE-2021-20330
Specific replication command with malformed oplog entries can crash secondaries
Vulnerability Description
An attacker with basic CRUD permissions on a replicated collection can run the applyOps command with specially malformed oplog entries, resulting in a potential denial of service on secondaries. This issue affects MongoDB Server v4.0 versions prior to 4.0.27; MongoDB Server v4.2 versions prior to 4.2.16; MongoDB Server v4.4 versions prior to 4.4.9.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
No credits recorded in the NVD database.
References
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Affected Vendor
MongoDB Inc.
View all reports →Affected Software
MongoDB Server
Vulnerable Versions:
4.0, 4.2, 4.4
Timeline
Official Publish:
December 15th, 2021
Last Modified:
September 16th, 2024
Added to House:
July 21st, 2026
CVSS Vectors
V3:
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H