Medium severity · published Dec 15, 2021
CVE-2021-20330
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…
6.5
CVSS
1.1%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 65% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
4.0.0 before 4.0.25; 4.2.0 before 4.2.14; 4.4.0 before 4.4.6 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-20330
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-20330
Issue Tracking
https://jira.mongodb.org/browse/SERVER-36263
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