CVE-2021-20330

Specific replication command with malformed oplog entries can crash secondaries

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.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.38%
Vendor Advisory mongodb.org
Affected: MongoDB Inc. MongoDB Server
Published at:
Updated at:

References

Link Tags
https://jira.mongodb.org/browse/SERVER-36263 patch vendor advisory issue tracking

Frequently Asked Questions

What is the severity of CVE-2021-20330?
CVE-2021-20330 has been scored as a medium severity vulnerability.
How to fix CVE-2021-20330?
To fix CVE-2021-20330, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-20330 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-20330 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-20330?
CVE-2021-20330 affects MongoDB Inc. MongoDB Server.
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