4.2Medium
Mongodb Mongodb
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 restrict authentication to other mechanisms. This could allow authentication through a method the administrator intended to disable.
What this means for your business
- It affects Mongodb. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
What to do
- 1Check whether your company or your suppliers run Mongodb, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 4.2 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N- CVSS v4
- 2.3
- Weakness
- CWE-863
- Assigned by
- cna@mongodb.com
Dates
- Published
- 2026-08-11
- Last modified
- 2026-09-16
- Sources
- NVD
Affected products
- Mongodb Mongodb8.2.0 - 8.2.12, 8.3.0 - 8.3.8, 9.0.0, 9.1.0
As listed in the NVD configuration data. Not a statement about your estate.