Red Hat Security Advisory: dovecot security update
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: ManageSieve: Denial of Service via crafted SASL initial response in AUTHENTICATE command (CVE-2025-59032) * dovecot: denial of service via crafted message before authentication (CVE-2026-27858) * dovecot: denial of service via specially crafted NOOP command (CVE-2026-27857) 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.
AI Analysis
Technical Summary
This advisory covers three denial of service vulnerabilities in Dovecot affecting Red Hat Enterprise Linux 9.4 and related distributions. CVE-2025-59032 involves a denial of service triggered by a crafted SASL initial response in the AUTHENTICATE command within ManageSieve. CVE-2026-27858 and CVE-2026-27857 describe denial of service conditions triggered by crafted messages before authentication and specially crafted NOOP commands, respectively. These vulnerabilities could allow an attacker to disrupt Dovecot services. Red Hat has issued updated packages to fix these issues as detailed in advisory RHSA-2026:17625.
Potential Impact
Successful exploitation of these vulnerabilities results in denial of service conditions on Dovecot servers, potentially disrupting email services. There is no indication of privilege escalation or data disclosure. The impact is limited to service availability.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9.4 and related variants that address these vulnerabilities. Users should apply the security update described in advisory RHSA-2026:17625 promptly to remediate these issues. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor.
Red Hat Security Advisory: dovecot security update
Description
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: ManageSieve: Denial of Service via crafted SASL initial response in AUTHENTICATE command (CVE-2025-59032) * dovecot: denial of service via crafted message before authentication (CVE-2026-27858) * dovecot: denial of service via specially crafted NOOP command (CVE-2026-27857) 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.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers three denial of service vulnerabilities in Dovecot affecting Red Hat Enterprise Linux 9.4 and related distributions. CVE-2025-59032 involves a denial of service triggered by a crafted SASL initial response in the AUTHENTICATE command within ManageSieve. CVE-2026-27858 and CVE-2026-27857 describe denial of service conditions triggered by crafted messages before authentication and specially crafted NOOP commands, respectively. These vulnerabilities could allow an attacker to disrupt Dovecot services. Red Hat has issued updated packages to fix these issues as detailed in advisory RHSA-2026:17625.
Potential Impact
Successful exploitation of these vulnerabilities results in denial of service conditions on Dovecot servers, potentially disrupting email services. There is no indication of privilege escalation or data disclosure. The impact is limited to service availability.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9.4 and related variants that address these vulnerabilities. Users should apply the security update described in advisory RHSA-2026:17625 promptly to remediate these issues. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:17625
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a946c
Added to database: 06/17/2026, 16:46:54 UTC
Last enriched: 06/26/2026, 01:02:48 UTC
Last updated: 08/01/2026, 19:17:56 UTC
Views: 43
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