CVE-2026-126838
Rust Driver public Client Debug output exposes CSFLE KMS master-key material
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.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| Rust Driver MongoDB |
≥ 3.9.0; < 3.9.1 (affected, semver) ≥ 3.8.0; < 3.8.2 (affected, semver) 3.7.0 (affected, semver) 3.6.0 (affected, semver) ≥ 3.5.0; < 3.5.2 (affected, semver) ≥ 3.4.0; < 3.4.1 (affected, semver) 3.3.0 (affected, semver) ≥ 3.2.0; < 3.2.5 (affected, semver) ≥ 3.1.0; < 3.1.1 (affected, semver) ≥ 3.0.0; < 3.0.1 (affected, semver) ≥ 2.8.0; < 2.8.2 (affected, semver) ≥ 2.7.0; < 2.7.1 (affected, semver) ≥ 2.6.0; < 2.6.1 (affected, semver) 2.5.0 (affected, semver) 2.4.0 (affected, semver) Other versions: unaffected |
CNA: mongodb |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 5.7 medium |
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N | CNA: mongodb |
| 3.1 / 5.5 medium |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N | CNA: mongodb |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://jira.mongodb.org/browse/RUST-2531CNA: mongodb
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