CVE-2026-18703
Improper Enforcement of Authentication Mechanism Restrictions in MongoDB Server Allows Use of Disabled Authentication Method
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- High
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Improper Enforcement of Authentication Mechanism Restrictions in MongoDB Server Allows Use of Disabled Authentication Method
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.
- Record
CVE-2026-18703- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-56861
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.
- Record
EUVD-2026-56861- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-h22h-g2cf-r8hr
An issue in MongoDB Server could allow a party with a valid client certificate and a...
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.
- Record
GHSA-h22h-g2cf-r8hr- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-18703- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSV
Improper Enforcement of Authentication Mechanism Restrictions in MongoDB Server Allows Use of Disabled Authentication Method
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.
- Record
CVE-2026-18703- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSVUBUNTU-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.
- Record
UBUNTU-CVE-2026-18703- CVSS 4.0
- 2.3 Low
CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 4.2 Medium
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N - Updated
- 2026-11-02
OSVBIT-mongodb-2026-18703 No score
Improper Enforcement of Authentication Mechanism Restrictions in MongoDB Server Allows Use of Disabled Authentication Method
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.
- Record
BIT-mongodb-2026-18703- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
mongodbBitnami |
8.2.0 up to 8.3.8, 9.0.0 up to 9.0.2 | 8.3.89.0.2 |
mongodbUbuntu:Pro:14.04:LTS |
All versions, plus listed versions 1:2.4.6-0ubuntu51:2.4.6-0ubuntu61:2.4.8-1ubuntu11:2.4.8-21:2.4.9-11:2.4.9-1ubuntu11:2.4.9-1ubuntu21:2.4.9-1ubuntu2+esm2 |
None known |
mongodbUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 1:2.6.10-0ubuntu11:2.6.10-0ubuntu1+esm2 |
None known |
mongodbUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 1:3.4.7-11:3.4.7-1ubuntu11:3.4.7-1ubuntu21:3.4.7-1ubuntu41:3.4.14-3ubuntu1 Show 7 moreShow less1:3.4.14-3ubuntu21:3.6.3-0ubuntu11:3.6.3-0ubuntu1.11:3.6.3-0ubuntu1.31:3.6.3-0ubuntu1.41:3.6.3-0ubuntu1.4+esm11:3.6.3-0ubuntu1.4+esm2 |
None known |
mongodbUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu21:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu51:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.21:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.31:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.3+esm1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-18703 is a low vulnerability (CVSS 2.3) in Mongodb, published August 11, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.14%, the 3rd percentile. Fixed in mongodb 8.3.8.