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 triggered by crafted SASL initial responses in the AUTHENTICATE command, crafted messages before authentication, and specially crafted NOOP commands. Red Hat has released security updates addressing these vulnerabilities in Red Hat Enterprise Linux 8.6 variants. The vulnerabilities are rated with an important security impact by Red Hat, and no known exploits are reported in the wild.
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 the ManageSieve service; 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 but do not indicate remote code execution or data compromise. Red Hat has issued updated Dovecot packages for Red Hat Enterprise Linux 8.6 variants to address these issues.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email service availability. There is no indication of privilege escalation, data leakage, or remote code execution. No known exploits in the wild have been reported.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 8.6 Extended Update Support Extension, Advanced Mission Critical Update Support, Update Services for SAP Solutions, and Telecommunications Update Service. Users should apply these official updates to remediate the vulnerabilities. For detailed update instructions, refer to Red Hat's advisory at https://access.redhat.com/articles/11258. Patch status is confirmed with official fixes available.
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 triggered by crafted SASL initial responses in the AUTHENTICATE command, crafted messages before authentication, and specially crafted NOOP commands. Red Hat has released security updates addressing these vulnerabilities in Red Hat Enterprise Linux 8.6 variants. The vulnerabilities are rated with an important security impact by Red Hat, and no known exploits are reported in the wild.
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 the ManageSieve service; 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 but do not indicate remote code execution or data compromise. Red Hat has issued updated Dovecot packages for Red Hat Enterprise Linux 8.6 variants to address these issues.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email service availability. There is no indication of privilege escalation, data leakage, or remote code execution. No known exploits in the wild have been reported.
Mitigation Recommendations
Red Hat has released updated Dovecot packages for Red Hat Enterprise Linux 8.6 Extended Update Support Extension, Advanced Mission Critical Update Support, Update Services for SAP Solutions, and Telecommunications Update Service. Users should apply these official updates to remediate the vulnerabilities. For detailed update instructions, refer to Red Hat's advisory at https://access.redhat.com/articles/11258. Patch status is confirmed with official fixes available.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:19453
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf799f87a2db092a8e1c
Added to database: 6/17/2026, 4:46:49 PM
Last enriched: 6/17/2026, 5:05:26 PM
Last updated: 6/17/2026, 6:23:31 PM
Views: 2
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