CVSS 4.0
5.7 mediumCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:NCVE-2026-126838 Rust Driver public Client Debug output exposes CSFLE KMS master-key material
Medium (5.7) in mongodb rust driver. EPSS 0.07% estimated probability of exploitation activity in the next 30 days.
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A MongoDB Rust Driver component that holds client-side field level encryption settings includes key management service credential material in its diagnostic formatting output without redaction. An application that records or displays this formatted output may place that material where a party with read access to the application's diagnostic output can see it, which may result in unintended disclosure of key material.
Severity
CVSS 3.1
5.5 mediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N- EPSS
- 0.07% estimated probability of exploitation activity in the next 30 days; 0th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- CISA's assessment (SSVC)
- Exploitation: none · Automatable: no · Technical impact: partial, assessed 2026-11-13. From CISA's Vulnrichment in the CVE List: whether it is exploited, whether exploiting it can be automated, and how much control it gives.
- CWE
- CWE-532 Insertion of Sensitive Information into Log File
- OWASP Top 10
- A09:2025 Logging & Alerting Failures
- Published
- Modified
- Assigned by
- mongodb (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
- mongodb:rust driver
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| MongoDB Rust Driver | from 3.9.0 before 3.9.1 |
| MongoDB Rust Driver | from 3.8.0 before 3.8.2 |
| MongoDB Rust Driver | 3.7.0 |
| MongoDB Rust Driver | 3.6.0 |
| MongoDB Rust Driver | from 3.5.0 before 3.5.2 |
| MongoDB Rust Driver | from 3.4.0 before 3.4.1 |
| MongoDB Rust Driver | 3.3.0 |
| MongoDB Rust Driver | from 3.2.0 before 3.2.5 |
| MongoDB Rust Driver | from 3.1.0 before 3.1.1 |
| MongoDB Rust Driver | from 3.0.0 before 3.0.1 |
| MongoDB Rust Driver | from 2.8.0 before 2.8.2 |
| MongoDB Rust Driver | from 2.7.0 before 2.7.1 |
| MongoDB Rust Driver | from 2.6.0 before 2.6.1 |
| MongoDB Rust Driver | 2.5.0 |
| MongoDB Rust Driver | 2.4.0 |
Attack patterns (CAPEC)
- CAPEC-215 Fuzzing for application mapping Likelihood: High · Severity: Low
The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.