CVE-2026-27856
Full vulnerability record from the local CVENow database.
Description
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.
Severity
MEDIUM
CVSS score
5.9
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-03-27 09:16:19.767000
Last modified
2026-10-26 21:10:00.170000
View original CVE JSON
{
"id": "CVE-2026-27856",
"sourceIdentifier": "[email protected]",
"published": "2026-03-27T09:16:19.767",
"lastModified": "2026-10-26T21:10:00.170",
"vulnStatus": "Modified",
"cveTags": [],
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{
"lang": "en",
"value": "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."
},
{
"lang": "es",
"value": "Las credenciales de Doveadm se verifican mediante comparación directa, lo cual es susceptible a un ataque de oráculo de tiempo. Un atacante puede usar esto para determinar las credenciales configuradas. Averiguar la credencial conducirá a un acceso total al componente afectado. Limite el acceso al puerto del servicio HTTP de doveadm, instale la versión corregida. No se conocen exploits disponibles públicamente."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Open-Xchange GmbH",
"product": "OX Dovecot Pro",
"defaultStatus": "unaffected",
"modules": [
"core"
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"source": "[email protected]",
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