MongoDBGHSA-frjf-h5jg-4v46
Heap buffer overflow via mid-scan command list growth in client topology monitoring
High8.3CVE-2026-96746 · Published Sep 24, 2026
### Impact 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. ### Patches Fixed in 1.30.12 and 2.5.5. ### Workarounds None. ### References https://jira.mongodb.org/browse/CDRIVER-6404
Affected versions
| Package | Affected | Fixed in |
|---|---|---|
| mongo-c-driver Product | >= 1.0.0, < 1.30.12 | 1.30.12 |
| >= 2.0.0, < 2.5.5 | 2.5.5 |
Details and references
- CVSS 4.0
- 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 from
- GitHub (reviewed advisory)
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