High severity · published Sep 8, 2026
CVE-2026-82064
Unauthenticated Denial of Service in MongoDB Server via Assertion Failure in Read Concern Processing on Replica Set Members
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
A security issue in MongoDB Server allows an unauthenticated network user to cause a denial of service on a specific type of replica set member. The server contains an assertion in its read concern processing logic that can be reached without authentication, and the assertion's assumptions about internal state do not hold for all member configurations, causing the server process to terminate.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 44% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
8.3.0 before 8.3.9; 8.0.0 before 8.0.30; 7.0.0 before 7.0.41 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-82064
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-82064
Vendor Advisory
https://jira.mongodb.org/browse/SERVER-130759
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