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.
https://github.com/mongodb/mongo-c-driver/security/advisories/GHSA-frjf-h5jg-4v46
https://github.com/mongodb/mongo-c-driver/releases/tag/2.5.5
https://github.com/mongodb/mongo-c-driver/releases/tag/1.30.12
Published: 2026-09-24
Updated: 2026-09-24
Base Score: 6.1
Vector: CVSS2#AV:N/AC:H/Au:N/C:N/I:P/A:C
Severity: Medium
Base Score: 6.5
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:H
Severity: Medium
Base Score: 8.3
Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
Severity: High
EPSS: 0.00366