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
Dovecot, a secure IMAP and POP3 server, contains three denial of service vulnerabilities. CVE-2025-59032 involves the ManageSieve component where a crafted SASL initial response in the AUTHENTICATE command can cause a denial of service. CVE-2026-27858 allows denial of service via a crafted message sent before authentication. CVE-2026-27857 involves denial of service triggered by a specially crafted NOOP command. These vulnerabilities affect Red Hat Enterprise Linux 9 and related CodeReady Linux Builder and Extended Update Support versions. Red Hat has issued an important security advisory (RHSA-2026:19364) with updated packages to remediate these issues.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot server, potentially disrupting email services. There is no indication of remote code execution or data compromise from the provided information. The impact is limited to service availability.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9 and related variants that address these denial of service vulnerabilities. Users should apply the security update described in Red Hat Advisory RHSA-2026:19364 as soon as possible. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor advisory.
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
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Dovecot, a secure IMAP and POP3 server, contains three denial of service vulnerabilities. CVE-2025-59032 involves the ManageSieve component where a crafted SASL initial response in the AUTHENTICATE command can cause a denial of service. CVE-2026-27858 allows denial of service via a crafted message sent before authentication. CVE-2026-27857 involves denial of service triggered by a specially crafted NOOP command. These vulnerabilities affect Red Hat Enterprise Linux 9 and related CodeReady Linux Builder and Extended Update Support versions. Red Hat has issued an important security advisory (RHSA-2026:19364) with updated packages to remediate these issues.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot server, potentially disrupting email services. There is no indication of remote code execution or data compromise from the provided information. The impact is limited to service availability.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9 and related variants that address these denial of service vulnerabilities. Users should apply the security update described in Red Hat Advisory RHSA-2026:19364 as soon as possible. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:19364
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf799f87a2db092a8e24
Added to database: 06/17/2026, 16:46:49 UTC
Last enriched: 06/25/2026, 23:45:29 UTC
Last updated: 07/31/2026, 19:24:46 UTC
Views: 38
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