CVE-2026-40205

An attacker that holds an OAuth2 token granting only part of the required scopes can authenticate, because when more than one scope is required in the configuration, the remote token validation paths accept a token that carries only one of them, while the local token validation path correctly requires all of them. The configured authorization policy is not enforced, so a token that was granted only part of the required permissions is accepted where it should have been rejected. Use local token validation where tokens can be validated locally. Update to non-vulnerable version. No publicly available exploits are known.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 12:16

Updated : 2026-09-03 18:13

NVD link : CVE-2026-40205

Mitre link : CVE-2026-40205

CVE.ORG link : CVE-2026-40205

JSON object : View

Products Affected

No product.

CWE

CWE-287

Improper Authentication

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