Red Hat Security Advisory: dovecot security update
Multiple denial of service vulnerabilities have been identified in Dovecot, an IMAP and POP3 server for Linux and UNIX-like systems. These issues include a crafted SASL initial response in the AUTHENTICATE command, a crafted message before authentication, and a specially crafted NOOP command. Red Hat has issued a security advisory with updates addressing these vulnerabilities in Red Hat Enterprise Linux 8.8 variants. The vulnerabilities are rated as having an important security impact.
AI Analysis
Technical Summary
This advisory addresses three denial of service vulnerabilities in Dovecot: CVE-2025-59032 involves a crafted SASL initial response in the AUTHENTICATE command affecting ManageSieve; 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 could cause service disruption. Red Hat has released updated packages for Red Hat Enterprise Linux 8.8 and related update services to remediate these issues.
Potential Impact
Successful exploitation of these vulnerabilities could result in denial of service conditions, causing the Dovecot service to become unavailable or unresponsive. This impacts the availability of email services relying on Dovecot for IMAP or POP3 access.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 8.8 and associated update services that address these vulnerabilities. Users should apply the provided security updates as detailed in the Red Hat advisory RHSA-2026:18053. Patch status is confirmed with official fixes available. No additional mitigation steps beyond applying the update are specified.
Red Hat Security Advisory: dovecot security update
Description
Multiple denial of service vulnerabilities have been identified in Dovecot, an IMAP and POP3 server for Linux and UNIX-like systems. These issues include a crafted SASL initial response in the AUTHENTICATE command, a crafted message before authentication, and a specially crafted NOOP command. Red Hat has issued a security advisory with updates addressing these vulnerabilities in Red Hat Enterprise Linux 8.8 variants. The vulnerabilities are rated as having an important security impact.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory addresses three denial of service vulnerabilities in Dovecot: CVE-2025-59032 involves a crafted SASL initial response in the AUTHENTICATE command affecting ManageSieve; 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 could cause service disruption. Red Hat has released updated packages for Red Hat Enterprise Linux 8.8 and related update services to remediate these issues.
Potential Impact
Successful exploitation of these vulnerabilities could result in denial of service conditions, causing the Dovecot service to become unavailable or unresponsive. This impacts the availability of email services relying on Dovecot for IMAP or POP3 access.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 8.8 and associated update services that address these vulnerabilities. Users should apply the provided security updates as detailed in the Red Hat advisory RHSA-2026:18053. Patch status is confirmed with official fixes available. No additional mitigation steps beyond applying the update are specified.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:18053
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a9401
Added to database: 06/17/2026, 16:46:54 UTC
Last enriched: 06/28/2026, 00:34:34 UTC
Last updated: 08/01/2026, 19:17:56 UTC
Views: 62
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