MEDIUM🇵🇱 Wersja polska

CVE-2026-33603

CVSS 6.8v3.1pub. 2026-05-12upd. 2026-05-18

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.

CVSS Vector
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
  • Dovecot

    APP
    Dovecot
    < 2.4.4
  • Open Xchange Dovecot

    APP
    Open-Xchange
    < 3.1.5
🔵
CHECK WITH VENDOR
No clear patch data available. Check vendor references.
CWE
References

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