High severity · published Aug 28, 2026
CVE-2026-40018
None None None No publicly available exploits are known
7.4
CVSS
0.3%
EPSS
No
On KEV
Description
None None None No publicly available exploits are known.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% 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 3.1.6 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-40018
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-40018
documentation.open-xchange.com
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json
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