Low severity · published Aug 28, 2026
CVE-2026-40204
None None None No publicly available exploits are known
3.1
CVSS
0.2%
EPSS
No
On KEV
Description
None None None No publicly available exploits are known.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 11% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OD
OX Dovecot CE · Open-Xchange GmbH
2.3.0 before 2.4.5 · source: vendor
OD
OX Dovecot Pro · Open-Xchange GmbH
2.3.0 before 2.3.22.2; 3.0.0 before 3.0.7; 3.1.0 before 3.1.6 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40204
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40204
documentation.open-xchange.com
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json
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