CVE-2026-27855
MEDIUM
6,8
Source: [email protected]
Attack Vector: network
Attack Complexity: high
Privileges Required: none
User Interaction: required
Scope: unchanged
Confidentiality: high
Integrity: high
Availability: none
Description
AI Translation Available
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.
EPSS (Exploit Prediction Scoring System)
Trend Analysis
EPSS (Exploit Prediction Scoring System)
Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.
EPSS Score
0,0004
Percentile
0,1th
Updated
EPSS Score Trend (Last 3 Days)
294
Authentication Bypass by Capture-replay
IncompleteCommon Consequences
Security Scopes Affected:
Access Control
Potential Impacts:
Gain Privileges Or Assume Identity
Applicable Platforms
All platforms may be affected
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/ox…