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 and a crafted SASL initial response in the AUTHENTICATE command; CVE-2026-27858 involves denial of service via a crafted message before authentication; and CVE-2026-27857 involves denial of service via a specially crafted NOOP command. These vulnerabilities can cause service disruption. Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 8 to fix these issues as detailed in advisory RHSA-2026:13830.
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 privilege escalation or data compromise. 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 8 that address these denial of service vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:13830 and the referenced article https://access.redhat.com/articles/11258 to remediate these issues. 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
Dovecot, a secure IMAP and POP3 server, contains three denial of service vulnerabilities: CVE-2025-59032 involves the ManageSieve component and a crafted SASL initial response in the AUTHENTICATE command; CVE-2026-27858 involves denial of service via a crafted message before authentication; and CVE-2026-27857 involves denial of service via a specially crafted NOOP command. These vulnerabilities can cause service disruption. Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 8 to fix these issues as detailed in advisory RHSA-2026:13830.
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 privilege escalation or data compromise. 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 8 that address these denial of service vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:13830 and the referenced article https://access.redhat.com/articles/11258 to remediate these issues. 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-2026:13830
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a9487
Added to database: 06/17/2026, 16:46:54 UTC
Last enriched: 06/26/2026, 01:09:10 UTC
Last updated: 08/01/2026, 10:58:26 UTC
Views: 95
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