RLSA-2026:80825
Important: dovecot security update
Published Oct 14, 2026 · updated Oct 14, 2026
Dovecot is an IMAP server for Linux and other UNIX-like systems, written primarily with security in mind. It also contains a small POP3 server, and supports e-mail in either the maildir or mbox format. The SQL drivers and authentication plug-ins are provided as subpackages. Security Fix(es): * dovecot: Dovecot: Denial of Service via IMAP ID command with excessive parameters (CVE-2026-42391) * dovecot: Dovecot: Authentication bypass via incorrect OAuth2 token validation (CVE-2026-73208) * dovecot: Dovecot: Denial of service via crafted email headers (CVE-2026-27852) * dovecot: Dovecot: Denial of Service via truncated quoted argument in ManageSieve (CVE-2026-40019) * dovecot: Dovecot: Denial of Service and potential message duplication via connection limit exhaustion (CVE-2026-33263) * dovecot: Dovecot: Denial of Service in ManageSieve login process (CVE-2026-33605) * dovecot: Dovecot: Arbitrary Code Execution via Sieve editheader use-after-free (CVE-2026-42007) * dovecot: Dovecot: MySQL multi-byte escaping wrong (CVE-2026-40018) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Code
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No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Oct 14, 2026 · OSV.dev
Detected
Dovecot is an IMAP server for Linux and other UNIX-like systems, written primarily with security in mind. It also contains a small POP3 server, and supports e-mail in either the maildir or mbox format. The SQL drivers and authentication plug-ins are provided as subpackages. Security Fix(es): * dovecot: Dovecot: Denial of Service via IMAP ID command with excessive parameters (CVE-2026-42391) * dove
Oct 14, 2026 · OSV.dev
Fix available
dovecot fixed in 1:2.3.16-18.el9_8.8
Oct 14, 2026 · OSV.dev
Fix available
dovecot fixed in 1:2.3.16-18.el9_8.8
Oct 14, 2026 · OSV.dev
Updated
Dovecot is an IMAP server for Linux and other UNIX-like systems, written primarily with security in mind. It also contains a small POP3 server, and supports e-mail in either the maildir or mbox format. The SQL drivers and authentication plug-ins are provided as subpackages. Security Fix(es): * dovecot: Dovecot: Denial of Service via IMAP ID command with excessive parameters (CVE-2026-42391) * dove
Affected
- Rocky Linux:9 dovecot0 → 1:2.3.16-18.el9_8.8