Medium severity · published Sep 24, 2026
CVE-2026-96746
Heap buffer overflow via mid-scan command list growth in client topology monitoring
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
An out-of-bounds write in the connection-monitoring logic of the MongoDB C Driver may allow an unauthenticated party who controls name resolution and the responses of the hosts named in a client's connection string to write beyond the end of a heap buffer. This may cause the application using the driver to terminate unexpectedly.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
MO
MongoDB · MongoDB
before 1.30.12; 2.0.0 before 2.5.5 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-96746
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-96746
github.com
https://github.com/mongodb/mongo-c-driver/releases/tag/1.30.12
github.com
https://github.com/mongodb/mongo-c-driver/releases/tag/2.5.5
github.com
https://github.com/mongodb/mongo-c-driver/security/advisories/GHSA-frjf-h5jg-4v46
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