Description
Attacker can use a specially crafted base64 exchange between Dovecot and Client to fake SCRAM TLS channel binding. This requires that the attacker is able to position itself between Dovecot and the client connection. If successful, the attacker can eavesdrop communications between Dovecot and client as MITM proxy. Install fixed version. No publicly available exploits are known.
Affected products
dovecot: dovecot; open-xchange: dovecot
References1
- documentation.open-xchange.com/dovecot/security/advisories/csaf… Vendor Advisory
Metrics
- CVSS 3.1
-
5.3
MEDIUM
Score source: NVD
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N - EPSS — exploit probability
- 0% percentile: 12 · as of 14 November 2026
- CWE
- CWE-99
Could this be exploited in your environment?
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