CVE-2026-126838
Rust Driver public Client Debug output exposes CSFLE KMS master-key material
Description
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.
INFO
Published Date :
Nov. 12, 2026, 7:17 p.m.
Last Modified :
Nov. 12, 2026, 7:17 p.m.
Remotely Exploit :
No
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | a39b4221-9bd0-4244-95fc-f3e2e07f1deb | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | a39b4221-9bd0-4244-95fc-f3e2e07f1deb | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Ensure key material is redacted in diagnostic output.
- Update the MongoDB Rust Driver to the latest version.
- Review application logging for sensitive data.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-126838.
| URL | Resource |
|---|---|
| https://jira.mongodb.org/browse/RUST-2531 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-126838 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-126838
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-126838 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-126838 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Nov. 12, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Added CWE CWE-532 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/126xxx/CVE-2026-126838.json">CVE-2026-126838</a> Added Reference https://jira.mongodb.org/browse/RUST-2531