CVE-2026-27858highCWE-400CWE-770

CVE-2026-27858: 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 7.5epss 0.8%
Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No publicly available exploits are known.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Affected products
Open-Xchange GmbH · OX Dovecot Pro
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