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 a crafted SASL initial response in the AUTHENTICATE command affecting ManageSieve; CVE-2026-27858 involves a denial of service triggered by a crafted message before authentication; and CVE-2026-27857 involves a denial of service via a specially crafted NOOP command. These vulnerabilities could allow an attacker to disrupt service availability. Red Hat has released security updates for Red Hat Enterprise Linux 10 and associated CodeReady Linux Builder and Extended Update Support versions to remediate these issues.
Potential Impact
The vulnerabilities allow denial of service attacks against the Dovecot server, potentially causing service interruptions. There is no indication of code execution or data compromise. The impact is limited to service availability degradation or disruption.
Mitigation Recommendations
Red Hat has released security updates that fix these vulnerabilities in Dovecot for Red Hat Enterprise Linux 10 and related products. Users should apply the provided updates as described in the Red Hat advisory RHSA-2026:19149. Patch status is confirmed as fixed in these updated packages. 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
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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 a crafted SASL initial response in the AUTHENTICATE command affecting ManageSieve; CVE-2026-27858 involves a denial of service triggered by a crafted message before authentication; and CVE-2026-27857 involves a denial of service via a specially crafted NOOP command. These vulnerabilities could allow an attacker to disrupt service availability. Red Hat has released security updates for Red Hat Enterprise Linux 10 and associated CodeReady Linux Builder and Extended Update Support versions to remediate these issues.
Potential Impact
The vulnerabilities allow denial of service attacks against the Dovecot server, potentially causing service interruptions. There is no indication of code execution or data compromise. The impact is limited to service availability degradation or disruption.
Mitigation Recommendations
Red Hat has released security updates that fix these vulnerabilities in Dovecot for Red Hat Enterprise Linux 10 and related products. Users should apply the provided updates as described in the Red Hat advisory RHSA-2026:19149. Patch status is confirmed as fixed in these updated packages. 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-2026:19149
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf799f87a2db092a8e2c
Added to database: 06/17/2026, 16:46:49 UTC
Last enriched: 06/26/2026, 00:58:50 UTC
Last updated: 08/01/2026, 07:17:57 UTC
Views: 111
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