An update for dovecot is now available for openEuler-22.03-LTS-SP4,openEuler-24.03-LTS,openEuler-24.03-LTS-SP1,openEuler-24.03-LTS-SP2,openEuler-24.03-LTS-SP3,openEuler-20.03-LTS-SP4 Security Advisory openeuler-security@openeuler.org openEuler security committee openEuler-SA-2026-1849 Final 1.0 1.0 2026-04-11 Initial 2026-04-11 2026-04-11 openEuler SA Tool V1.0 2026-04-11 dovecot security update An update for dovecot is now available for openEuler-22.03-LTS-SP4,openEuler-24.03-LTS,openEuler-24.03-LTS-SP1,openEuler-24.03-LTS-SP2,openEuler-24.03-LTS-SP3,openEuler-20.03-LTS-SP4 Dovecot is an IMAP server for Linux/UNIX-like systemsa wrapper package that will just handle common things for all versioned dovecot packages. Security Fix(es): Dovecot has provided a script to use for attachment to text conversion. This script unsafely handles zip-style attachments. Attacker can use specially crafted OOXML documents to cause unintended files on the system to be indexed and subsequently ending up in FTS indexes. Do not use the provided script, instead, use something else like FTS tika. No publicly available exploits are known.(CVE-2025-59031) 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 version. No publicly available exploits are known.(CVE-2025-59032) When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or slash has been added to allowed characters, path traversal can happen if the domain component is directory partial. This allows inadvertently reading /etc/passwd (or some other path which ends with passwd). If this file contains passwords, it can be used to authenticate wrongly, or if this is userdb, it can unexpectly make system users appear valid users. Upgrade to fixed version, or use different authentication scheme that does not rely on paths. Alternatively you can also ensure that the per-domain passwd files are in some other location, such as /etc/dovecot/auth/%d. No publicly available exploits are known.(CVE-2026-0394) Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. An attacker able to observe an OTP exchange is able to log in as the user. If authentication happens over unsecure connection, switch to SCRAM protocol. Alternatively ensure the communcations are secured, and if possible switch to OAUTH2 or SCRAM. No publicly available exploits are known.(CVE-2026-27855) 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 http service port, install fixed version. No publicly available exploits are known.(CVE-2026-27856) Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage. Longer commands will result in client disconnection. This 1 MB can be left allocated for longer time periods by not sending the command ending LF. So attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Install fixed version, there is no other remediation. No publicly available exploits are known.(CVE-2026-27857) 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 publicly available exploits are known.(CVE-2026-27858) A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably formatted mail message causes mail delivery process to consume large amounts of CPU time. Use MTA capabilities to limit RFC 2231 MIME parameters in mail messages, or upgrade to fixed version where the processing is limited. No publicly available exploits are known.(CVE-2026-27859) An update for dovecot is now available for master/openEuler-22.03-LTS-SP4,openEuler-24.03-LTS,openEuler-24.03-LTS-SP1,openEuler-24.03-LTS-SP2,openEuler-24.03-LTS-SP3,openEuler-20.03-LTS-SP4. openEuler Security has rated this update as having a security impact of high. A Common Vunlnerability Scoring System(CVSS)base score,which gives a detailed severity rating, is available for each vulnerability from the CVElink(s) in the References section. High dovecot https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2025-59031 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2025-59032 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2026-0394 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2026-27855 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2026-27856 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2026-27857 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2026-27858 https://www.openeuler.org/en/security/cve/detail/?cveId=CVE-2026-27859 https://nvd.nist.gov/vuln/detail/CVE-2025-59031 https://nvd.nist.gov/vuln/detail/CVE-2025-59032 https://nvd.nist.gov/vuln/detail/CVE-2026-0394 https://nvd.nist.gov/vuln/detail/CVE-2026-27855 https://nvd.nist.gov/vuln/detail/CVE-2026-27856 https://nvd.nist.gov/vuln/detail/CVE-2026-27857 https://nvd.nist.gov/vuln/detail/CVE-2026-27858 https://nvd.nist.gov/vuln/detail/CVE-2026-27859 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 dovecot-2.3.15-7.oe2203sp4.aarch64.rpm dovecot-debuginfo-2.3.15-7.oe2203sp4.aarch64.rpm dovecot-debugsource-2.3.15-7.oe2203sp4.aarch64.rpm dovecot-devel-2.3.15-7.oe2203sp4.aarch64.rpm dovecot-help-2.3.15-7.oe2203sp4.aarch64.rpm dovecot-2.3.20-4.oe2403.aarch64.rpm dovecot-debuginfo-2.3.20-4.oe2403.aarch64.rpm dovecot-debugsource-2.3.20-4.oe2403.aarch64.rpm dovecot-devel-2.3.20-4.oe2403.aarch64.rpm dovecot-help-2.3.20-4.oe2403.aarch64.rpm dovecot-2.3.20-4.oe2403sp1.aarch64.rpm dovecot-debuginfo-2.3.20-4.oe2403sp1.aarch64.rpm dovecot-debugsource-2.3.20-4.oe2403sp1.aarch64.rpm dovecot-devel-2.3.20-4.oe2403sp1.aarch64.rpm dovecot-help-2.3.20-4.oe2403sp1.aarch64.rpm dovecot-2.3.20-4.oe2403sp2.aarch64.rpm dovecot-debuginfo-2.3.20-4.oe2403sp2.aarch64.rpm dovecot-debugsource-2.3.20-4.oe2403sp2.aarch64.rpm dovecot-devel-2.3.20-4.oe2403sp2.aarch64.rpm dovecot-help-2.3.20-4.oe2403sp2.aarch64.rpm dovecot-2.3.20-4.oe2403sp3.aarch64.rpm dovecot-debuginfo-2.3.20-4.oe2403sp3.aarch64.rpm dovecot-debugsource-2.3.20-4.oe2403sp3.aarch64.rpm dovecot-devel-2.3.20-4.oe2403sp3.aarch64.rpm dovecot-help-2.3.20-4.oe2403sp3.aarch64.rpm dovecot-2.3.15-7.oe2003sp4.aarch64.rpm dovecot-debuginfo-2.3.15-7.oe2003sp4.aarch64.rpm dovecot-debugsource-2.3.15-7.oe2003sp4.aarch64.rpm dovecot-devel-2.3.15-7.oe2003sp4.aarch64.rpm dovecot-help-2.3.15-7.oe2003sp4.aarch64.rpm dovecot-2.3.15-7.oe2203sp4.src.rpm dovecot-2.3.20-4.oe2403.src.rpm dovecot-2.3.20-4.oe2403sp1.src.rpm dovecot-2.3.20-4.oe2403sp2.src.rpm dovecot-2.3.20-4.oe2403sp3.src.rpm dovecot-2.3.15-7.oe2003sp4.src.rpm dovecot-2.3.15-7.oe2203sp4.x86_64.rpm dovecot-debuginfo-2.3.15-7.oe2203sp4.x86_64.rpm dovecot-debugsource-2.3.15-7.oe2203sp4.x86_64.rpm dovecot-devel-2.3.15-7.oe2203sp4.x86_64.rpm dovecot-help-2.3.15-7.oe2203sp4.x86_64.rpm dovecot-2.3.20-4.oe2403.x86_64.rpm dovecot-debuginfo-2.3.20-4.oe2403.x86_64.rpm dovecot-debugsource-2.3.20-4.oe2403.x86_64.rpm dovecot-devel-2.3.20-4.oe2403.x86_64.rpm dovecot-help-2.3.20-4.oe2403.x86_64.rpm dovecot-2.3.20-4.oe2403sp1.x86_64.rpm dovecot-debuginfo-2.3.20-4.oe2403sp1.x86_64.rpm dovecot-debugsource-2.3.20-4.oe2403sp1.x86_64.rpm dovecot-devel-2.3.20-4.oe2403sp1.x86_64.rpm dovecot-help-2.3.20-4.oe2403sp1.x86_64.rpm dovecot-2.3.20-4.oe2403sp2.x86_64.rpm dovecot-debuginfo-2.3.20-4.oe2403sp2.x86_64.rpm dovecot-debugsource-2.3.20-4.oe2403sp2.x86_64.rpm dovecot-devel-2.3.20-4.oe2403sp2.x86_64.rpm dovecot-help-2.3.20-4.oe2403sp2.x86_64.rpm dovecot-2.3.20-4.oe2403sp3.x86_64.rpm dovecot-debuginfo-2.3.20-4.oe2403sp3.x86_64.rpm dovecot-debugsource-2.3.20-4.oe2403sp3.x86_64.rpm dovecot-devel-2.3.20-4.oe2403sp3.x86_64.rpm dovecot-help-2.3.20-4.oe2403sp3.x86_64.rpm dovecot-2.3.15-7.oe2003sp4.x86_64.rpm dovecot-debuginfo-2.3.15-7.oe2003sp4.x86_64.rpm dovecot-debugsource-2.3.15-7.oe2003sp4.x86_64.rpm dovecot-devel-2.3.15-7.oe2003sp4.x86_64.rpm dovecot-help-2.3.15-7.oe2003sp4.x86_64.rpm Dovecot has provided a script to use for attachment to text conversion. This script unsafely handles zip-style attachments. Attacker can use specially crafted OOXML documents to cause unintended files on the system to be indexed and subsequently ending up in FTS indexes. Do not use the provided script, instead, use something else like FTS tika. No publicly available exploits are known. 2026-04-11 CVE-2025-59031 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 Medium 4.3 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 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 version. No publicly available exploits are known. 2026-04-11 CVE-2025-59032 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 High 7.5 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 When dovecot has been configured to use per-domain passwd files, and they are placed one path component above /etc, or slash has been added to allowed characters, path traversal can happen if the domain component is directory partial. This allows inadvertently reading /etc/passwd (or some other path which ends with passwd). If this file contains passwords, it can be used to authenticate wrongly, or if this is userdb, it can unexpectly make system users appear valid users. Upgrade to fixed version, or use different authentication scheme that does not rely on paths. Alternatively you can also ensure that the per-domain passwd files are in some other location, such as /etc/dovecot/auth/%d. No publicly available exploits are known. 2026-04-11 CVE-2026-0394 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 Medium 5.3 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 Dovecot OTP authentication is vulnerable to replay attack under specific conditions. If auth cache is enabled, and username is altered in passdb, then OTP credentials can be cached so that same OTP reply is valid. An attacker able to observe an OTP exchange is able to log in as the user. If authentication happens over unsecure connection, switch to SCRAM protocol. Alternatively ensure the communcations are secured, and if possible switch to OAUTH2 or SCRAM. No publicly available exploits are known. 2026-04-11 CVE-2026-27855 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 Medium 6.8 AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 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 http service port, install fixed version. No publicly available exploits are known. 2026-04-11 CVE-2026-27856 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 High 7.4 AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 Sending "NOOP (((...)))" command with 4000 parenthesis open+close results in ~1MB extra memory usage. Longer commands will result in client disconnection. This 1 MB can be left allocated for longer time periods by not sending the command ending LF. So attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Attacker could connect possibly from even a single IP and create 1000 connections to allocate 1 GB of memory, which would likely result in reaching VSZ limit and killing the process and its other proxied connections. Install fixed version, there is no other remediation. No publicly available exploits are known. 2026-04-11 CVE-2026-27857 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 Medium 4.3 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 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 publicly available exploits are known. 2026-04-11 CVE-2026-27858 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 High 7.5 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849 A mail message containing excessive amount of RFC 2231 MIME parameters causes LMTP to use too much CPU. A suitably formatted mail message causes mail delivery process to consume large amounts of CPU time. Use MTA capabilities to limit RFC 2231 MIME parameters in mail messages, or upgrade to fixed version where the processing is limited. No publicly available exploits are known. 2026-04-11 CVE-2026-27859 openEuler-22.03-LTS-SP4 openEuler-24.03-LTS openEuler-24.03-LTS-SP1 openEuler-24.03-LTS-SP2 openEuler-24.03-LTS-SP3 openEuler-20.03-LTS-SP4 Medium 5.3 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L dovecot security update 2026-04-11 https://www.openeuler.org/zh/security/security-bulletins/detail/?id=openEuler-SA-2026-1849