Atlas SQL ODBC CVE-2026-19503

Exploitation requires two simultaneous prerequisites: (1) the victim must use MONGODB-OIDC as the configured authentication mechanism when connecting to a MongoDB deployment - standard SCRAM, username/password, or x.509 authentication modes are entirely unaffected; and (2) the attacker must control the MongoDB deployment the victim connects to, achieved either by hosting a rogue server and inducing the user to connect (social engineering, phishing, misconfigured connection string) or by performing network-level interception of the OIDC discovery request. Code execution as a specific outcome additionally requires that the victim's operating system has a registered protocol handler for the scheme the attacker injects - this condition is OS-dependent and non-universal, making credential exposure the more broadly applicable harm. Users whose MongoDB clients connect exclusively to verified, organization-managed deployments over controlled networks are not at risk, and the MONGODB-OIDC mode must be explicitly configured rather than being a default.

The vendor-supplied CVSS 4.0 vector (AV:N/AC:L/AT:P/PR:N/UI:N) yields a base score of 6.3 (Medium). The AT:P qualifier accurately captures that exploitation requires a specific attack prerequisite - attacker control of the MongoDB deployment the victim connects to, or successful network-level interception of the OIDC discovery request. However, the UI:N metric appears inconsistent with the description's explicit 'user induced to connect' language; UI:P (passive user interaction) better reflects the social engineering step required, and security teams should factor this into triage. The vulnerability is not listed in CISA KEV, no EPSS data was available for this CVE ID, and no proof-of-concept has been identified, all of which support a moderate-priority rather than emergency-priority classification. Impact is bounded by user context - code execution, where achievable, occurs without privilege escalation - and the credential exposure outcome is contingent on what OIDC token the user holds. The combination of social engineering prerequisite, specific MONGODB-OIDC configuration requirement, and OS protocol handler dependency makes real-world exploitation meaningfully harder than raw CVSS network vector suggests.

An attacker hosts a rogue MongoDB instance and configures its OIDC issuer to serve a discovery document containing a malicious URI scheme - such as ms-msdt:// or a custom file:// path - as the token_endpoint value. A developer or data analyst is deceived via phishing, a misconfigured connection string, or DNS manipulation into connecting to this deployment using MONGODB-OIDC authentication; the unpatched driver then passes the unvalidated URI to the Windows or macOS default protocol handler, which may invoke a registered local application that either exfiltrates the user's OIDC tokens or executes attacker-supplied arguments. No public proof-of-concept has been identified at time of analysis.