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.

CVSS v3 4.2 MEDIUM

4.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/SERVER-127863	Vendor Advisory Issue Tracking

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mongodb:mongodb::::::::
	cpe:2.3:a:mongodb:mongodb::::::::
	cpe:2.3:a:mongodb:mongodb:9.0.0:alpha0:::-:-::
	cpe:2.3:a:mongodb:mongodb:9.0.0:alpha1:::-:-::
	cpe:2.3:a:mongodb:mongodb:9.1.0:alpha0:::-:-::

History

16 Sep 2026, 15:19

Type	Values Removed	Values Added
First Time		Mongodb Mongodb mongodb
References	~~() https://jira.mongodb.org/browse/SERVER-127863 -~~	() https://jira.mongodb.org/browse/SERVER-127863 - Vendor Advisory, Issue Tracking
CPE		cpe:2.3:a:mongodb:mongodb:9.0.0:alpha1:::-:-:: cpe:2.3:a:mongodb:mongodb:9.1.0:alpha0:::-:-:: cpe:2.3:a:mongodb:mongodb:9.0.0:alpha0:::-:-:: cpe:2.3:a:mongodb:mongodb::::::::

Information

Published : 2026-08-11 19:17

Updated : 2026-09-16 15:19

NVD link : CVE-2026-18703

Mitre link : CVE-2026-18703

CVE.ORG link : CVE-2026-18703

JSON object : View

Products Affected

mongodb

mongodb

CWE

CWE-863

Incorrect Authorization

{"id": "CVE-2026-18703", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-18703", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-08-11T20:28:22.222939Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "cna@mongodb.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 4.2, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N", "integrityImpact": "LOW", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "LOW"}, "impactScore": 2.5, "exploitabilityScore": 1.6}], "cvssMetricV40": [{"type": "Secondary", "source": "cna@mongodb.com", "cvssData": {"Safety": "NOT_DEFINED", "version": "4.0", "Recovery": "NOT_DEFINED", "baseScore": 2.3, "Automatable": "NOT_DEFINED", "attackVector": "NETWORK", "baseSeverity": "LOW", "valueDensity": "NOT_DEFINED", "vectorString": "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", "exploitMaturity": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "userInteraction": "NONE", "attackComplexity": "HIGH", "attackRequirements": "PRESENT", "privilegesRequired": "LOW", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "LOW", "integrityRequirement": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "availabilityRequirement": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "LOW", "confidentialityRequirement": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "cna@mongodb.com", "affectedData": [{"vendor": "MongoDB", "product": "MongoDB Server", "versions": [{"status": "affected", "version": "8.3.0", "lessThan": "8.3.8", "versionType": "semver"}], "defaultStatus": "unaffected"}]}], "published": "2026-08-11T19:17:24.900", "references": [{"url": "https://jira.mongodb.org/browse/SERVER-127863", "tags": ["Vendor Advisory", "Issue Tracking"], "source": "cna@mongodb.com"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Secondary", "source": "cna@mongodb.com", "description": [{"lang": "en", "value": "CWE-863"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-09-16T15:19:02.303", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:mongodb:mongodb:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "7BCD6B05-9FD5-4283-A2AC-8B625425597F", "versionEndIncluding": "8.2.12", "versionStartIncluding": "8.2.0"}, {"criteria": "cpe:2.3:a:mongodb:mongodb:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "6EE4503A-F53C-432E-9DDB-F488DD989E8A", "versionEndExcluding": "8.3.8", "versionStartIncluding": "8.3.0"}, {"criteria": "cpe:2.3:a:mongodb:mongodb:9.0.0:alpha0:*:*:-:-:*:*", "vulnerable": true, "matchCriteriaId": "0FB52026-6C88-4401-84B5-3A070F0906D4"}, {"criteria": "cpe:2.3:a:mongodb:mongodb:9.0.0:alpha1:*:*:-:-:*:*", "vulnerable": true, "matchCriteriaId": "8D32A105-731C-493E-8CBF-639204CDAC7C"}, {"criteria": "cpe:2.3:a:mongodb:mongodb:9.1.0:alpha0:*:*:-:-:*:*", "vulnerable": true, "matchCriteriaId": "D56E512D-83F8-4D51-8690-E92F6A006822"}], "operator": "OR"}]}], "sourceIdentifier": "cna@mongodb.com"}