What is CVE-2026-18703?

CVE-2026-18703 is a medium-severity vulnerability in Mongodb Server, classified under Incorrect Authorization. CVSS score: 4.2/10. Published 2026-08-11.

How severe is CVE-2026-18703?

Medium severity. CVSS v3 base score is 4.2 out of 10.

Auth bypass in Mongodb Server

CVE-2026-18703

An issue in MongoDB Server could allow a party with a valid client certificate and a corresponding user account to authenticate using a certificate-based authentication method, even when an administrator has configured the server to restri…

Vulnerability class: Broken Access Control

CVSS v3 metric

CVSS v3 base score 4.2 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N.

Affected products

Mongodb Server — versions 8.3.0

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

References

cna@mongodb.com

Frequently asked questions

What is CVE-2026-18703?: CVE-2026-18703 is a medium-severity vulnerability in Mongodb Server, classified under Incorrect Authorization. CVSS score: 4.2/10. Published 2026-08-11.
How severe is CVE-2026-18703?: Medium severity. CVSS v3 base score is 4.2 out of 10.