CVE-2026-27856highCWE-208CWE-287

CVE-2026-27856: high-severity vulnerability in Open-Xchange GmbH OX Dovecot Pro

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.4epss 0.4%
Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm http service port, install fixed version. No publicly available exploits are known.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Affected products
Open-Xchange GmbH · OX Dovecot Pro
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