Vulnerabilities

Vulnerability · CVE-2026-114654

BSON output corruption via out-of-range binary subtype bypassing UUID and OldBinary guards

Published Oct 22, 2026 · catalog updated Oct 22, 2026 · MongoDB C# Driver

Open the advisory

Exploitation likelihood is not on this record for CVE-2026-114654. A missing EPSS score is not a low risk. Compare MongoDB C# Driver with the linked advisory before you change production.

Gaps on this record

  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
  • EPSS is missing. A missing score is not a low risk.
Severity
Medium6.9
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
Not in the current FIRST EPSS dataset
Remediation
Advisory link
Affected products
vendor MongoDB C# Driver

A numeric-type conversion flaw in the BSON handling library of the MongoDB C# Driver allows an out-of-range binary subtype value supplied through untrusted textual input to bypass the library's binary-element integrity checks. When such a value is later encoded, it is narrowed to a smaller wire representation, producing binary elements that misdeclare their type or length. An unauthenticated party able to supply text parsed by an affected application can cause it to emit and persist malformed binary data, which subsequent readers either reject with an error or silently interpret as shorter than the data that was validated.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • vendor MongoDB C# Driverversion unspecified

How to fix CVE-2026-114654

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

Exploitation likelihood is not on this record for CVE-2026-114654. A missing EPSS score is not a low risk. Compare MongoDB C# Driver with the linked advisory before you change production.

Which versions are affected?

Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-681. EPSS is absent from the current FIRST dataset. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 22, 2026 · CVE.org

    Updated

    A numeric-type conversion flaw in the BSON handling library of the MongoDB C# Driver allows an out-of-range binary subtype value supplied through untrusted textual input to bypass the library's binary-element integrity checks. When such a value is later encoded, it is narrowed to a smaller wire representation, producing binary elements that misdeclare their type or length. An unauthenticated party

  2. Oct 23, 2026 · BSI CERT-Bund

    Detected

    CVE-2026-114654 is listed by MongoDB C# Treiber: Mehrere Schwachstellen.

Sources

  • BSI CERT-BundGovernment advisoryCVE-2026-114654

    MongoDB C# Treiber: Mehrere Schwachstellen

    wid.cert-bund.de
  • CVE.orgVulnerability recordCVE-2026-114654

    A numeric-type conversion flaw in the BSON handling library of the MongoDB C# Driver allows an out-of-range binary subtype value supplied through untrusted textual input to bypass the library's binary-element integrity checks. When such a value is later encoded, it is narrowed to

    cve.org

References

Freshness

Last verified in this catalog Oct 23, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.