CVE-2026-81528 — MEDIUM (5.4)

Vulnerability Description

A MongoDB C# driver document-replacement code path omits the element-name/shape validation that the equivalent write paths apply, so a value supplied as a replacement is forwarded to the server without neutralization of query-language special elements. An application that passes untrusted, loosely-typed input as a replacement value therefore allows that input to be interpreted by the database as update logic rather than as data, executing under the application's own database credentials. Applications using strongly-typed document mappings are not affected.

CVSS Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

LOW

Integrity

LOW

Availability

NONE

Related Weaknesses (CWE)

CWE-943

References

FAQ

What is CVE-2026-81528?

CVE-2026-81528 is a vulnerability with a CVSS score of 5.4 (MEDIUM). A MongoDB C# driver document-replacement code path omits the element-name/shape validation that the equivalent write paths apply, so a value supplied as a replacement is forwarded to the server withou...

How severe is CVE-2026-81528?

CVE-2026-81528 has been rated MEDIUM with a CVSS base score of 5.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-81528?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.