PT-2026-40025 · Dovecot · Dovecot

Published 2026-05-12 · Updated 2026-06-02 · CVE-2026-33603

Positive Technologies (AI Summary)

CVSS v3.1

6.8

Medium

Base vector

AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Name of the Vulnerable Software and Affected Versions Dovecot versions prior to 2.4.4-1.1

Description An attacker positioned between Dovecot and the client connection can use a specially crafted base64 exchange to fake SCRAM TLS channel binding. This allows the attacker to act as a MITM (Man-in-the-Middle) proxy and eavesdrop on communications between the client and the server.

Recommendations Update to version 2.4.4-1.1.

Fix

Weakness Enumeration

CWE-99

Related Identifiers

CVE-2026-33603

OPENSUSE-SU-2026:10766-1

USN-8365-1

Affected Products

Dovecot

References · 21

• https://osv.dev/vulnerability/UBUNTU-CVE-2026-33603 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-40020 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-8365-1 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-33603 · Vendor Advisory
• https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.json · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-33603 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-42006 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2026-33603 · Vendor Advisory
• https://osv.dev/vulnerability/openSUSE-SU-2026:10766-1 · Vendor Advisory
• https://osv.dev/vulnerability/USN-8365-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-40016 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-33603 · Security Note
• https://cve.org/CVERecord?id=CVE-2026-33603 · Security Note
• https://ubuntu.com/security/CVE-2026-27851 · Vendor Advisory
• https://suse.com/security/cve/CVE-2026-42006 · Note