CLSA-2026-1778255734 dovecot: Fix of 2 CVEs

CVE-2026-27858: bound managesieve-login AUTHENTICATE initial response size to prevent memory exhaustion DoS before authentication - CVE-2025-59032: fix managesieve-login crash when AUTHENTICATE command did not finish on the first call due to literal SASL initial response...

CLSA-2026-1778173027 dovecot: Fix of CVE-2026-27858

CVE-2026-27858: fix unbounded memory allocation in managesieve-login when AUTHENTICATE initial response literal size is excessively large...

CLSA-2026-1778172123 dovecot: Fix of CVE-2026-27858

CVE-2026-27858: fix unbounded memory allocation in managesieve-login when AUTHENTICATE initial response literal size is excessively large...

dovecot: ManageSieve: Denial of Service via crafted SASL initial response in AUTHENTICATE command

A flaw was found in ManageSieve. A remote attacker can exploit this vulnerability by sending a crafted SASL Simple Authentication and Security Layer initial response during the AUTHENTICATE command. This can cause the ManageSieve service to crash repeatedly, leading to a Denial of Service DoS for...

dovecot: denial of service via crafted message before authentication

A flaw was found in dovecot. An unauthenticated and remote attacker can send a crafted message that causes managesieve to allocate an excessive amount of memory, forcing managesieve-login to be unavailable by repeatedly crashing the process, resulting in a denial of service...

dovecot: ManageSieve: Denial of Service via crafted SASL initial response in AUTHENTICATE command

A flaw was found in ManageSieve. A remote attacker can exploit this vulnerability by sending a crafted SASL Simple Authentication and Security Layer initial response during the AUTHENTICATE command. This can cause the ManageSieve service to crash repeatedly, leading to a Denial of Service DoS for...

dovecot: denial of service via crafted message before authentication

A flaw was found in dovecot. An unauthenticated and remote attacker can send a crafted message that causes managesieve to allocate an excessive amount of memory, forcing managesieve-login to be unavailable by repeatedly crashing the process, resulting in a denial of service...

dovecot security update

1:2.3.21-16.1 - fix CVE-2026-27858: denial of service via crafted message before authentication RHEL-161625 - fix CVE-2025-59032: ManageSieve: Denial of Service via crafted SASL initial response in AUTHENTICATE command RHEL-162273 - fix CVE-2026-27857: denial of service via specially crafted NOOP...

dovecot: denial of service via crafted message before authentication

A flaw was found in dovecot. An unauthenticated and remote attacker can send a crafted message that causes managesieve to allocate an excessive amount of memory, forcing managesieve-login to be unavailable by repeatedly crashing the process, resulting in a denial of service...

Security update for dovecot22

This update for dovecot22 fixes the following issues: CVE-2025-59031: decode2text.sh OOXML extraction may follow symlinks and read unintended files during indexing bsc1260895. CVE-2025-59032: pigeonhole: ManageSieve panic occurs with sieve-connect as a client bsc1260902. CVE-2026-27855: OTP drive...

SUSE SLES16 Security Update : dovecot24 (SUSE-SU-2026:21208-1)

The remote SUSE Linux SLES16 / SLESSAP16 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:21208-1 advisory. - Update to v2.4.3 - CVE-2025-59028: Invalid base64 authentication can cause DoS for other logins bsc1260894. - CVE-2025-59031:...

📄 Dovecot ManageSieve Crash Denial of Service

This Metasploit auxiliary module targets a denial of service vulnerability in the Dovecot ManageSieve service, where improper handling of authentication requests can lead to service crashes. Affects Dovecot CE core 2.4.0-2.4.2 and Dovecot Pro core 3.1.0-3.1.2. Fixed in versions 2.4.3 and 3.1.3...

OPENSUSE-SU-2026:20554-1 Security update for dovecot24

This update for dovecot24 fixes the following issues: - Update to v2.4.3 - CVE-2025-59028: Invalid base64 authentication can cause DoS for other logins bsc1260894. - CVE-2025-59031: decode2text.sh OOXML extraction may follow symlinks and read unintended files during indexing bsc1260895. -...

Important: dovecot

Issue Overview: Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the credential will lead into full access to the affected component. Limit access to the doveadm ht...

Amazon Linux 2023 : dovecot, dovecot-devel, dovecot-mysql (ALAS2023-2026-1570)

It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2023-2026-1570 advisory. Doveadm credentials are verified using direct comparison which is susceptible to timing oracle attack. An attacker can use this to determine the configured credentials. Figuring out the...

OESA-2026-1849 dovecot security update

Dovecot is an IMAP server for Linux/UNIX-like systemsa wrapper package that will just handle common things for all versioned dovecot packages. Security Fixes: Dovecot has provided a script to use for attachment to text conversion. This script unsafely handles zip-style attachments. Attacker can u...

SUSE CVE-2025-59032

ManageSieve AUTHENTICATE command crashes when using literal as SASL initial response. This can be used to crash ManageSieve service repeatedly, making it unavailable for other users. Control access to ManageSieve port, or disable the service if it's not needed. Alternatively upgrade to a fixed...

SUSE CVE-2026-27858

Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No public...

Linux Distros Unpatched Vulnerability : CVE-2026-27858

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force...

Linux Distros Unpatched Vulnerability : CVE-2025-59032

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available. - ManageSieve AUTHENTICATE command crashes when using literal as SASL initial response. This can be used to crash ManageSieve service repeatedly, making it...