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…
- Published
- Updated
- Reserved
- Assigned by
- OX
Description
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.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| OXCNA (assigner) | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N |
| NVDNVD · Deferred | 3.1 | Medium5.9 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.21% · top 89% of all CVEs (6 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.9.
Weakness
Affected products
Open-Xchange GmbH · OX Dovecot Pro
- affected 2.3.11.2 – < 2.3.22.2
- affected 3.0.0 – < 3.0.7
- affected 3.1.0 – < 3.1.6
Open-Xchange GmbH · OX Dovecot CE
- affected 2.3.11.2 – < 2.4.5
References (1)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-40205)Record last updated .