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 widely used IMAP and POP3 server, contains multiple denial of service vulnerabilities. CVE-2025-59032 involves the ManageSieve component where a crafted SASL initial response in the AUTHENTICATE command can cause denial of service. 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 have been addressed in updated Dovecot packages provided by Red Hat for their Enterprise Linux 10.0 Extended Update Support variants. The advisory references specific bugzilla entries and provides updated package versions for remediation.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot server, potentially disrupting mail services. There is no indication of remote code execution or data disclosure. The impact is limited to service availability degradation or interruption.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 10.0 Extended Update Support that address these denial of service vulnerabilities. Users should apply these official updates as detailed in the Red Hat advisory RHSA-2026:17602. Patch status is confirmed with official fixes available. No additional mitigation steps are specified beyond applying the vendor-provided updates.
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
Dovecot, a widely used IMAP and POP3 server, contains multiple denial of service vulnerabilities. CVE-2025-59032 involves the ManageSieve component where a crafted SASL initial response in the AUTHENTICATE command can cause denial of service. 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 have been addressed in updated Dovecot packages provided by Red Hat for their Enterprise Linux 10.0 Extended Update Support variants. The advisory references specific bugzilla entries and provides updated package versions for remediation.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot server, potentially disrupting mail services. There is no indication of remote code execution or data disclosure. The impact is limited to service availability degradation or interruption.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 10.0 Extended Update Support that address these denial of service vulnerabilities. Users should apply these official updates as detailed in the Red Hat advisory RHSA-2026:17602. Patch status is confirmed with official fixes available. No additional mitigation steps are specified beyond applying the vendor-provided updates.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:17602
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a9476
Added to database: 06/17/2026, 16:46:54 UTC
Last enriched: 06/26/2026, 01:02:54 UTC
Last updated: 08/01/2026, 19:17:56 UTC
Views: 135
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