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.
Published:Aug 28, 2026
Last Modified:Sep 1, 2026
EPS:Aug 28, 2026
EPSS Score:0.00179
CVSS Score:5.9
Affected Products
Vendor
Product
Action
Vendor
Open-xchange
Product
Ox Dovecot Ce
Open-xchange
Ox Dovecot Ce
Vendor
Open-xchange
Product
Ox Dovecot Pro
Open-xchange
Ox Dovecot Pro
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
Related CVEs
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
