CVE-2026-42006
Fixed in a distro release EPSS <1%CVSS 4.3
An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass the limit. Using excessive bracing, attacker can cause memory usage up to configured memory limit. Install fixed version, or configure vsz_limit for imap process to low value. No publicly available exploits are known.
Products: Open-Xchange GmbH OX Dovecot Pro, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10.0 Extended Update Support, Red Hat Enterprise Linux 7 Extended Lifecycle Support, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On, Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On, Red Hat Enterprise Linux 8.8 Telecommunications Update Service, Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions, Red Hat Enterprise Linux 9, Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions, Red Hat Enterprise Linux 9.6 Extended Update Support, Red Hat Enterprise Linux 6
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| AlmaLinux 10 | dovecot | 1:2.3.21-19.el10_2.1 |
| AlmaLinux 10 | dovecot-devel | 1:2.3.21-19.el10_2.1 |
| AlmaLinux 10 | dovecot-mysql | 1:2.3.21-19.el10_2.1 |
| AlmaLinux 10 | dovecot-pgsql | 1:2.3.21-19.el10_2.1 |
| AlmaLinux 10 | dovecot-pigeonhole | 1:2.3.21-19.el10_2.1 |
| AlmaLinux 8 | dovecot | 1:2.3.16-8.el8_10 |
| AlmaLinux 8 | dovecot-devel | 1:2.3.16-8.el8_10 |
| AlmaLinux 8 | dovecot-mysql | 1:2.3.16-8.el8_10 |
| AlmaLinux 8 | dovecot-pgsql | 1:2.3.16-8.el8_10 |
| AlmaLinux 8 | dovecot-pigeonhole | 1:2.3.16-8.el8_10 |
| AlmaLinux 9 | dovecot | 1:2.3.16-18.el9_8.1 |
| AlmaLinux 9 | dovecot-devel | 1:2.3.16-18.el9_8.1 |
| AlmaLinux 9 | dovecot-mysql | 1:2.3.16-18.el9_8.1 |
| AlmaLinux 9 | dovecot-pgsql | 1:2.3.16-18.el9_8.1 |
| AlmaLinux 9 | dovecot-pigeonhole | 1:2.3.16-18.el9_8.1 |
| Alpine 3.23 | dovecot | 2.4.4-r0 |
| Alpine 3.24 | dovecot | 2.4.4-r0 |
| Debian 12 | dovecot | 1:2.3.19.1+dfsg1-2.1+deb12u6 |
| Debian 13 | dovecot | 1:2.4.1+dfsg1-6+deb13u6 |
| Debian 14 | dovecot | 1:2.4.4+dfsg1-1 |
| Red Hat Enterprise Linux 10.2 | dovecot | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-debuginfo | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-debugsource | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-devel | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-mysql | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-mysql-debuginfo | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-pgsql | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-pgsql-debuginfo | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-pigeonhole | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 10.2 | dovecot-pigeonhole-debuginfo | 1:2.3.21-19.el10_2.1 |
| Red Hat Enterprise Linux 8 | dovecot | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-debuginfo | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-debugsource | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-devel | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-mysql | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-mysql-debuginfo | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pgsql | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pgsql-debuginfo | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pigeonhole | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 8 | dovecot-pigeonhole-debuginfo | 1:2.3.16-8.el8_10 |
| Red Hat Enterprise Linux 9 | dovecot | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-debuginfo | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-debugsource | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-devel | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-mysql | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-mysql-debuginfo | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-pgsql | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-pgsql-debuginfo | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-pigeonhole | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux 9 | dovecot-pigeonhole-debuginfo | 1:2.3.16-18.el9_8.1 |
| Red Hat Enterprise Linux eus 10.0 | dovecot | 1:2.3.21-16.el10_0.2 |
| Red Hat rhel aus 8.4 | dovecot | 1:2.3.8-9.el8_4.2 |
| Red Hat rhel aus 8.6 | dovecot | 1:2.3.16-2.el8_6.2 |
| Red Hat rhel e4s 8.8 | dovecot | 1:2.3.16-3.el8_8.2 |
| Red Hat rhel e4s 9.2 | dovecot | 1:2.3.16-8.el9_2.3 |
| Red Hat rhel e4s 9.4 | dovecot | 1:2.3.16-11.el9_4.3 |
| Red Hat rhel els 7 | dovecot | 1:2.2.36-8.el7_9.2 |
| Red Hat rhel eus 9.6 | dovecot | 1:2.3.16-15.el9_6.2 |
| Red Hat rhel eus long life 8.4 | dovecot | 1:2.3.8-9.el8_4.2 |
| Red Hat rhel eus long life 8.6 | dovecot | 1:2.3.16-2.el8_6.2 |
| Red Hat rhel tus 8.8 | dovecot | 1:2.3.16-3.el8_8.2 |
| Rocky Linux 10 | dovecot | 1:2.3.21-19.el10_2.1 |
| Rocky Linux 8 | dovecot | 1:2.3.16-8.el8_10 |
| Rocky Linux 9 | dovecot | 1:2.3.16-18.el9_8.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 12 SP5-LTSS | dovecot22 | 2.2.31-19.37.2 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server 16.0 | dovecot24 | 2.4.4-160000.1.1 |
| SUSE Linux Enterprise Server LTSS Extended Security 12 SP5 | dovecot22 | 2.2.31-19.37.2 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | dovecot23 | 2.3.21.1-150200.76.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | dovecot24 | 2.4.4-160000.1.1 |
| Ubuntu 16.04 LTS | dovecot | no fix |
| Ubuntu 18.04 LTS | dovecot | no fix |
| Ubuntu 20.04 LTS | dovecot | no fix |
| Ubuntu 22.04 LTS | dovecot | 1:2.3.16+dfsg1-3ubuntu2.9 |
| Ubuntu 24.04 LTS | dovecot | 1:2.3.21+dfsg1-2ubuntu6.5 |
| Ubuntu 25.10 | dovecot | 1:2.4.1+dfsg1-5ubuntu4.2 |
| Ubuntu 26.04 LTS | dovecot | 1:2.4.2+dfsg1-3ubuntu2.1 |
| Ubuntu Pro 14.04 LTS | dovecot | no fix |
| openSUSE Leap 16.0 | dovecot24 | 2.4.4-160000.1.1 |
| openSUSE Tumbleweed | dovecot24 | 2.4.4-1.1 |