CVE-2026-33605
An unauthenticated attacker can crash the ManageSieve login process by sending a small malformed command before authenticating. If running in high-security mode (default for community releases), only the attacker's own connection is terminated. If running in high-performance mode (default for Pro releases), all connections handled by the same managesieve-login process are terminated. Repeating the attack can cause denial of service for Sieve script management. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.45%
- Percentil entre todas las CVEs puntuadas: 37
- Fecha de la puntuación: 5/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1190Exploit Public-Facing Applicationinitial access90 % - Impacto principal
T1499.002Service Exhaustion Floodimpact85 %
AV:N/PR:N/UI:N indica red sin autenticación (T1190). CWE-400 y descripción confirman DoS por crash del proceso login (T1499.002) al enviar comando malformado.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
⚠ Inferidas por IA a partir de la descripción — NVD aún no ha analizado esta CVE; no son CPE verificados.
CWE
- CWE-400
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-33605",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-33605",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "yes"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-08-28T14:42:10.586486Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security@open-xchange.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security@open-xchange.com",
"affectedData": [
{
"vendor": "Open-Xchange GmbH",
"modules": [
"core"
],
"product": "OX Dovecot Pro",
"versions": [
{
"status": "affected",
"version": "2.3.0",
"lessThan": "2.3.22.2",
"versionType": "semver"
},
{
"status": "affected",
"version": "3.0.0",
"lessThan": "3.0.7",
"versionType": "semver"
},
{
"status": "affected",
"version": "3.1.0",
"lessThan": "3.1.6",
"versionType": "semver"
}
],
"defaultStatus": "unaffected"
},
{
"vendor": "Open-Xchange GmbH",
"modules": [
"core"
],
"product": "OX Dovecot CE",
"versions": [
{
"status": "affected",
"version": "2.3.0",
"lessThan": "2.4.5",
"versionType": "semver"
}
],
"defaultStatus": "unaffected"
}
]
}
],
"published": "2026-08-28T12:16:27.740",
"references": [
{
"url": "https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0003.json",
"source": "security@open-xchange.com"
}
],
"vulnStatus": "Deferred",
"weaknesses": [
{
"type": "Secondary",
"source": "security@open-xchange.com",
"description": [
{
"lang": "en",
"value": "CWE-400"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "An unauthenticated attacker can crash the ManageSieve login process by sending a small malformed command before authenticating. If running in high-security mode (default for community releases), only the attacker's own connection is terminated. If running in high-performance mode (default for Pro releases), all connections handled by the same managesieve-login process are terminated. Repeating the attack can cause denial of service for Sieve script management. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version. No publicly available exploits are known."
}
],
"lastModified": "2026-09-03T18:13:44.643",
"sourceIdentifier": "security@open-xchange.com"
}