CVE-2026-81530

KMS credential disclosure via unredacted settings serialization

Published Aug 27, 2026 · Updated Aug 27, 2026

Sensitive-data exposure in the MongoDB .NET/C# Driver 2.10.0 through 3.11.0 allows local users to recover KMS credentials. The human-readable client-settings serializer includes KMS-provider credential values verbatim rather than applying the redaction used for other secret fields. Exploitation requires access to application logs, diagnostic output, or a process memory dump; exposed credentials can decrypt protected field data.

CVSS severity6.8
Medium
EPSS probability0.07%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sensitive-data exposure in the MongoDB .NET/C# Driver 2.10.0 through 3.11.0 allows local users to recover KMS credentials. The human-readable client-settings serializer includes KMS-provider credential values verbatim rather than applying the redaction used for other secret fields. Exploitation requires access to application logs, diagnostic output, or a process memory dump; exposed credentials can decrypt protected field data.

The record

CVE
CVE-2026-81530
Published
Aug 27, 2026
Updated
Aug 27, 2026
Vendor
MongoDB
Product
MongoDB .NET/C# Driver
Classifications
CWE-532, T1552.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 27, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.10.0 <3.11.1

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

MongoDB · MongoDB .NET/C# Driverversion=2.10.0 <3.11.1

Published CVSS scores

6.8MongoDBCVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N
5.6MongoDBCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-532Insertion of Sensitive Information into Log File
T1552.001Credentials In Files

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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