{"id":"CVE-2026-18703","title":"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 rest…","summary":"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 rest…","severity":"medium","cvss":4.2,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N","cwe":["CWE-863"],"vendor":"mongodb","product":"mongodb","affected":["mongodb >= 8.2.0, <= 8.2.12","mongodb >= 8.3.0, < 8.3.8","mongodb = 9.0.0","mongodb = 9.1.0"],"patched":["mongodb 8.3.8"],"published":"2026-08-11","updated":"2026-09-16","sourceUpdated":"2026-09-16T15:19:02.303","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-18703","references":[{"url":"https://jira.mongodb.org/browse/SERVER-127863","label":"cna@mongodb.com"}],"tags":["nvd"],"epss":0.00115,"epssPercentile":0.01761,"ingestedAt":"2026-08-29T19:41:16.000Z","slug":"CVE-2026-18703","body":"## Overview\n\nAn 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.\n\n## Affected\n\n- `mongodb >= 8.2.0, <= 8.2.12`\n- `mongodb >= 8.3.0, < 8.3.8`\n- `mongodb = 9.0.0`\n- `mongodb = 9.1.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `mongodb 8.3.8`","depth":"sunlit","depthScore":23,"depthScoreParts":{"impact":23.1,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}