Quick answers
- Is CVE-2026-103965 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-103965 being exploited in the wild.
- How severe is CVE-2026-103965?
- Medium severity, with a CVSS score of 5.4, published 13 October 2026.
- Which products and versions are affected?
- MongoDB Server before 7.0.45, 8.0.34, 8.3.13, 9.0.4, 9.1.0-rc1025.
- Is there a fix for CVE-2026-103965?
- Yes: fixed in 7.0.45, 8.0.34, 8.3.13, 9.0.4, 9.1.0-rc0, 9.1.0-rc1025. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-103965 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-103965?
- Check whether you run MongoDB Server at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 7.0.45, 8.0.34, 8.3.13, 9.0.4, 9.1.0-rc0, 9.1.0-rc1025
Technical details
The $bucket aggregation stage deserializes boundary and default values by re-parsing a BSON $switch expression, causing $literal-wrapped values with dollar-prefixed strings (e.g., "$color" or "$$ROOT") to be misinterpreted as field-path or variable expressions instead of remaining constants. An authenticated user with read access can trigger this via crafted aggregation queries to extract unintended field values. The vulnerability requires authentication and specific query construction but affects the integrity of data access controls.
Affected products
- MongoDB Server before 7.0.45, 8.0.34, 8.3.13, 9.0.4, 9.1.0-rc1025
Timeline
- 2026-10-13: disclosed
- 2026-10-12: patched