Vulnerability · Published Oct 13, 2026 · Assigned by mongodb
CVE-2026-103965Fixed values in MongoDB Server $bucket stage may be misread as field references
Medium 5.4
In plain English
A medium-severity code injection in MongoDB Server from MongoDB. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities).
Severity (CVSS 3.1)5.4Medium
Exploit odds (30 days)0.1%top 95.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
An issue in MongoDB Server's aggregation framework can cause certain constant values to be handled incorrectly during internal query rewriting. Under certain conditions, an authenticated user with read access may receive field values in aggregation output that the query did not intend to return.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| MongoDB | MongoDB Server | 8.3.0 – before 8.3.138.0 – before 8.0.347.0 – before 7.0.459.0 – before 9.0.4 |
Weakness: CWE-94 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N