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 include issues in the ManageSieve SASL authentication process, crafted messages before authentication, and specially crafted NOOP commands. Red Hat has released security updates addressing these vulnerabilities in Red Hat Enterprise Linux 10 and related products. The vulnerabilities are rated as important by Red Hat Product Security.
AI Analysis
Technical Summary
This advisory covers 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 the Dovecot service to become unavailable. Red Hat has issued updated packages for Red Hat Enterprise Linux 10 and related distributions to fix these issues.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email services relying on IMAP, POP3, or ManageSieve protocols. There is no indication of privilege escalation or data compromise in the advisory.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 10 and related variants that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:19149 and the referenced article https://access.redhat.com/articles/11258. No additional mitigations are specified or required beyond applying the official update.
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 include issues in the ManageSieve SASL authentication process, crafted messages before authentication, and specially crafted NOOP commands. Red Hat has released security updates addressing these vulnerabilities in Red Hat Enterprise Linux 10 and related products. The vulnerabilities are rated as important by Red Hat Product Security.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers 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 the Dovecot service to become unavailable. Red Hat has issued updated packages for Red Hat Enterprise Linux 10 and related distributions to fix these issues.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email services relying on IMAP, POP3, or ManageSieve protocols. There is no indication of privilege escalation or data compromise in the advisory.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 10 and related variants that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:19149 and the referenced article https://access.redhat.com/articles/11258. No additional mitigations 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-2026:19149
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf799f87a2db092a8e2c
Added to database: 6/17/2026, 4:46:49 PM
Last enriched: 6/17/2026, 5:05:12 PM
Last updated: 6/17/2026, 5:56:47 PM
Views: 2
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