Bug 2525548 (CVE-2026-40205) - CVE-2026-40205 dovecot: Dovecot: Authorization bypass via partially valid OAuth2 token
Summary: CVE-2026-40205 dovecot: Dovecot: Authorization bypass via partially valid OAu...
Keywords:
Status: NEW
Alias: CVE-2026-40205
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
URL:
Whiteboard:
Depends On: 2526682
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-08-28 11:22 UTC by OSIDB Bzimport
Modified: 2026-09-01 07:27 UTC (History)
2 users (show)

Fixed In Version:
Clone Of:
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Description OSIDB Bzimport 2026-08-28 11:22:13 UTC
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.


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