dovecot: Dovecot is an IMAP server for Linux and other UNIX-like systems, written primarily with security in mind
CVE-2026-27852 is fixed in 12 products on 1 platform, first by RHSA-2026:79371, released August 28, 2026. It is not reported as exploited. Patch Radar priority: High.
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.
Where it's fixed
| Product | Fixed in | Fix | Released |
|---|---|---|---|
| Linux | |||
| dovecot · Debian 12.15 (bookworm) | 1:2.3.19.1+dfsg1-2.1+deb12u7 | DEBIAN-CVE-2026-27852 | Sep 10, 2026 |
| dovecot · Debian 13.5 (trixie) | 1:2.4.1+dfsg1-6+deb13u7 | DEBIAN-CVE-2026-27852 | Sep 10, 2026 |
| dovecot · Debian 14 | 1:2.4.5+dfsg1-1 | DEBIAN-CVE-2026-27852 | Sep 10, 2026 |
| dovecot · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot · RHEL 10 | 2.3.21-19.el10_2.8 | RHSA-2026:79371 | Aug 28, 2026 |
| dovecot · RHEL 8 | 1:2.3.16-16.el8_10 | RHSA-2026:76763 | Oct 6, 2026 |
| dovecot · RHEL 9 | 1:2.3.16-18.el9_8.8 | RHSA-2026:80825 | Oct 13, 2026 |
| dovecot · almalinux 10 | 1:2.3.21-19.el10_2.8 | ALSA-2026:79371 | Oct 8, 2026 |
| dovecot · almalinux 8 | 1:2.3.16-16.el8_10 | ALSA-2026:76763 | Oct 6, 2026 |
| dovecot · almalinux 9 | 1:2.3.16-18.el9_8.8 | ALSA-2026:80825 | Nov 7, 2026 |
| dovecot · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot · ol 10 | 1:2.3.21-19.el10_2.8 | ELSA-2026-79371 | Oct 8, 2026 |
| dovecot · ol 8 | 1:2.3.16-16.el8_10 | ELSA-2026-76763 | Oct 6, 2026 |
| dovecot · ol 9 | 1:2.3.16-18.el9_8.8 | ELSA-2026-80825 | Nov 7, 2026 |
| dovecot · rocky 10 | 1:2.3.21-19.el10_2.8 | RLSA-2026:79371 | Nov 7, 2026 |
| dovecot · rocky 8 | 1:2.3.16-16.el8_10 | RLSA-2026:76763 | Oct 7, 2026 |
| dovecot · rocky 9 | 1:2.3.16-18.el9_8.8 | RLSA-2026:80825 | Nov 7, 2026 |
| dovecot-debuginfo · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-debuginfo · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-debugsource · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-debugsource · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-devel · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-devel · RHEL 8 | 1:2.3.16-16.el8_10 | RHSA-2026:76763 | Oct 6, 2026 |
| dovecot-devel · RHEL 9 | 1:2.3.16-18.el9_8.8 | RHSA-2026:80825 | Oct 13, 2026 |
| dovecot-devel · almalinux 10 | 1:2.3.21-19.el10_2.8 | ALSA-2026:79371 | Oct 8, 2026 |
| dovecot-devel · almalinux 8 | 1:2.3.16-16.el8_10 | ALSA-2026:76763 | Oct 6, 2026 |
| dovecot-devel · almalinux 9 | 1:2.3.16-18.el9_8.8 | ALSA-2026:80825 | Nov 7, 2026 |
| dovecot-devel · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-devel · ol 10 | 1:2.3.21-19.el10_2.8 | ELSA-2026-79371 | Oct 8, 2026 |
| dovecot-devel · ol 8 | 1:2.3.16-16.el8_10 | ELSA-2026-76763 | Oct 6, 2026 |
| dovecot-devel · ol 9 | 1:2.3.16-18.el9_8.8 | ELSA-2026-80825 | Nov 7, 2026 |
| dovecot-mysql · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-mysql · RHEL 8 | 1:2.3.16-16.el8_10 | RHSA-2026:76763 | Oct 6, 2026 |
| dovecot-mysql · RHEL 9 | 1:2.3.16-18.el9_8.8 | RHSA-2026:80825 | Oct 13, 2026 |
| dovecot-mysql · almalinux 10 | 1:2.3.21-19.el10_2.8 | ALSA-2026:79371 | Oct 8, 2026 |
| dovecot-mysql · almalinux 8 | 1:2.3.16-16.el8_10 | ALSA-2026:76763 | Oct 6, 2026 |
| dovecot-mysql · almalinux 9 | 1:2.3.16-18.el9_8.8 | ALSA-2026:80825 | Nov 7, 2026 |
| dovecot-mysql · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-mysql · ol 10 | 1:2.3.21-19.el10_2.8 | ELSA-2026-79371 | Oct 8, 2026 |
| dovecot-mysql · ol 8 | 1:2.3.16-16.el8_10 | ELSA-2026-76763 | Oct 6, 2026 |
| dovecot-mysql · ol 9 | 1:2.3.16-18.el9_8.8 | ELSA-2026-80825 | Nov 7, 2026 |
| dovecot-mysql-debuginfo · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-mysql-debuginfo · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-pgsql · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-pgsql · RHEL 8 | 1:2.3.16-16.el8_10 | RHSA-2026:76763 | Oct 6, 2026 |
| dovecot-pgsql · RHEL 9 | 1:2.3.16-18.el9_8.8 | RHSA-2026:80825 | Oct 13, 2026 |
| dovecot-pgsql · almalinux 10 | 1:2.3.21-19.el10_2.8 | ALSA-2026:79371 | Oct 8, 2026 |
| dovecot-pgsql · almalinux 8 | 1:2.3.16-16.el8_10 | ALSA-2026:76763 | Oct 6, 2026 |
| dovecot-pgsql · almalinux 9 | 1:2.3.16-18.el9_8.8 | ALSA-2026:80825 | Nov 7, 2026 |
| dovecot-pgsql · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-pgsql · ol 10 | 1:2.3.21-19.el10_2.8 | ELSA-2026-79371 | Oct 8, 2026 |
| dovecot-pgsql · ol 8 | 1:2.3.16-16.el8_10 | ELSA-2026-76763 | Oct 6, 2026 |
| dovecot-pgsql · ol 9 | 1:2.3.16-18.el9_8.8 | ELSA-2026-80825 | Nov 7, 2026 |
| dovecot-pgsql-debuginfo · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-pgsql-debuginfo · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-pigeonhole · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-pigeonhole · RHEL 8 | 1:2.3.16-16.el8_10 | RHSA-2026:76763 | Oct 6, 2026 |
| dovecot-pigeonhole · RHEL 9 | 1:2.3.16-18.el9_8.8 | RHSA-2026:80825 | Oct 13, 2026 |
| dovecot-pigeonhole · almalinux 10 | 1:2.3.21-19.el10_2.8 | ALSA-2026:79371 | Oct 8, 2026 |
| dovecot-pigeonhole · almalinux 8 | 1:2.3.16-16.el8_10 | ALSA-2026:76763 | Oct 6, 2026 |
| dovecot-pigeonhole · almalinux 9 | 1:2.3.16-18.el9_8.8 | ALSA-2026:80825 | Nov 7, 2026 |
| dovecot-pigeonhole · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot-pigeonhole · ol 10 | 1:2.3.21-19.el10_2.8 | ELSA-2026-79371 | Oct 8, 2026 |
| dovecot-pigeonhole · ol 8 | 1:2.3.16-16.el8_10 | ELSA-2026-76763 | Oct 6, 2026 |
| dovecot-pigeonhole · ol 9 | 1:2.3.16-18.el9_8.8 | ELSA-2026-80825 | Nov 7, 2026 |
| dovecot-pigeonhole-debuginfo · Fedora 43 | 1:2.4.5-1.fc43 | FEDORA-2026-E8A6485109 | Sep 10, 2026 |
| dovecot-pigeonhole-debuginfo · amzn 2023 | 1:2.3.20-1.amzn2023.0.4 | ALAS2023-2026-3109 | Sep 28, 2026 |
| dovecot23 · sles 15.6 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 | Sep 14, 2026 |
| dovecot23 · sles 15.7 | 2.3.21.1-150200.76.1 | SUSE-SU-2026:4139-1 | Sep 14, 2026 |
| dovecot24 · opensuse-leap 16.0 | 2.4.4-160000.2.1 | OPENSUSE-SU-2026:21720-1 | Sep 1, 2026 |
| dovecot24 · sles 16.0 | 2.4.4-160000.2.1 | SUSE-SU-2026:23595-1 | Sep 1, 2026 |
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