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CVE-2026-27855

Estado: AnalizadaMedia (5.9)—

Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. An attacker able to observe an OTP exchange is able to log in as the user. If authentication happens over unsecure connection, switch to SCRAM protocol. Alternatively ensure the communcations are secured, and if possible switch to OAUTH2 or SCRAM. No publicly available exploits are known.

CVSS

Probabilidad de explotación (EPSS)

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).

Tecnologías afectadas (2)

Dovecot — DovecotOpen-xchange — Dovecot

CWE

Referencias

JSON original (NVD)

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  "id": "CVE-2026-27855",
  "cveTags": [],
  "metrics": {
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          "role": "CISA Coordinator",
          "options": [
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          "timestamp": "2026-03-27T19:39:33.275509Z"
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  "published": "2026-03-27T09:16:19.610",
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  "lastModified": "2026-06-17T10:27:47.980",
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