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 a crafted SASL initial response in the AUTHENTICATE command affecting ManageSieve (CVE-2025-59032), a crafted message before authentication (CVE-2026-27858), and a specially crafted NOOP command (CVE-2026-27857). These vulnerabilities could allow an attacker to cause denial of service conditions. Red Hat has issued a security update addressing these issues in Dovecot packages for Red Hat Enterprise Linux 9.2 and related variants.
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 a crafted message sent before authentication; and CVE-2026-27857 involves a specially crafted NOOP command. These issues could be exploited to cause denial of service. Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9.2 and related distributions to address these vulnerabilities. The advisory references Red Hat Product Security errata RHSA-2026:17628 for detailed remediation instructions.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email service availability for affected systems. There is no indication of remote 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 9.2 and related variants that fix these denial of service vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:17628 and the referenced article https://access.redhat.com/articles/11258. No additional mitigations are specified by the vendor. Patch status is confirmed as an official fix available from Red Hat.
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 a crafted SASL initial response in the AUTHENTICATE command affecting ManageSieve (CVE-2025-59032), a crafted message before authentication (CVE-2026-27858), and a specially crafted NOOP command (CVE-2026-27857). These vulnerabilities could allow an attacker to cause denial of service conditions. Red Hat has issued a security update addressing these issues in Dovecot packages for Red Hat Enterprise Linux 9.2 and related variants.
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 a crafted message sent before authentication; and CVE-2026-27857 involves a specially crafted NOOP command. These issues could be exploited to cause denial of service. Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 9.2 and related distributions to address these vulnerabilities. The advisory references Red Hat Product Security errata RHSA-2026:17628 for detailed remediation instructions.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email service availability for affected systems. There is no indication of remote 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 9.2 and related variants that fix these denial of service vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:17628 and the referenced article https://access.redhat.com/articles/11258. No additional mitigations are specified by the vendor. Patch status is confirmed as an official fix available from Red Hat.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:17628
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a943a
Added to database: 06/17/2026, 16:46:54 UTC
Last enriched: 06/28/2026, 00:36:14 UTC
Last updated: 08/01/2026, 19:17:56 UTC
Views: 89
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