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 contains three denial of service vulnerabilities: CVE-2025-59032 involves the ManageSieve plugin 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 enables denial of service through a specially crafted NOOP command. These issues affect Red Hat Enterprise Linux 9.6 Extended Update Support and related CodeReady Linux Builder and other variants. Red Hat has released updated packages to remediate these vulnerabilities as detailed in advisory RHSA-2026:17626.
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 code execution or data disclosure. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9.6 Extended Update Support and related products that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:17626 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are specified or required beyond applying the official update.
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 contains three denial of service vulnerabilities: CVE-2025-59032 involves the ManageSieve plugin 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 enables denial of service through a specially crafted NOOP command. These issues affect Red Hat Enterprise Linux 9.6 Extended Update Support and related CodeReady Linux Builder and other variants. Red Hat has released updated packages to remediate these vulnerabilities as detailed in advisory RHSA-2026:17626.
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 code execution or data disclosure. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9.6 Extended Update Support and related products that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:17626 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are specified or required beyond applying the official update.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:17626
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a9444
Added to database: 06/17/2026, 16:46:54 UTC
Last enriched: 06/26/2026, 01:02:44 UTC
Last updated: 07/31/2026, 19:24:46 UTC
Views: 60
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