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 plugin via crafted SASL initial response during authentication, denial of service via crafted messages before authentication, and denial of service through specially crafted NOOP commands. The vulnerabilities affect Red Hat Enterprise Linux 8.4 versions with Dovecot packages. Red Hat has issued a security advisory with updates addressing these issues.
AI Analysis
Technical Summary
This advisory covers three denial of service vulnerabilities in Dovecot: CVE-2025-59032 involves the ManageSieve plugin where a crafted SASL initial response in the AUTHENTICATE command can cause denial of service. CVE-2026-27858 allows denial of service via a crafted message before authentication. CVE-2026-27857 involves denial of service through a specially crafted NOOP command. These vulnerabilities affect Red Hat Enterprise Linux 8.4 distributions with Dovecot 2.3.8-9.el8_4.1 packages. The advisory references fixes included in updated packages and provides links for applying these updates.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot server, potentially disrupting email services. There is no indication of privilege escalation or data compromise in the advisory. The impact is limited to service availability.
Mitigation Recommendations
Red Hat has released updated Dovecot packages (version 2.3.8-9.el8_4.1) for Red Hat Enterprise Linux 8.4 Extended Update Support and Advanced Update Support that address these vulnerabilities. Users should apply these official updates as detailed in the Red Hat advisory RHSA-2026:19455. Patch status is confirmed by the vendor advisory. No additional mitigation steps are indicated.
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 plugin via crafted SASL initial response during authentication, denial of service via crafted messages before authentication, and denial of service through specially crafted NOOP commands. The vulnerabilities affect Red Hat Enterprise Linux 8.4 versions with Dovecot packages. Red Hat has issued a security advisory with updates addressing these issues.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers three denial of service vulnerabilities in Dovecot: CVE-2025-59032 involves the ManageSieve plugin where a crafted SASL initial response in the AUTHENTICATE command can cause denial of service. CVE-2026-27858 allows denial of service via a crafted message before authentication. CVE-2026-27857 involves denial of service through a specially crafted NOOP command. These vulnerabilities affect Red Hat Enterprise Linux 8.4 distributions with Dovecot 2.3.8-9.el8_4.1 packages. The advisory references fixes included in updated packages and provides links for applying these updates.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot server, potentially disrupting email services. There is no indication of privilege escalation or data compromise in the advisory. The impact is limited to service availability.
Mitigation Recommendations
Red Hat has released updated Dovecot packages (version 2.3.8-9.el8_4.1) for Red Hat Enterprise Linux 8.4 Extended Update Support and Advanced Update Support that address these vulnerabilities. Users should apply these official updates as detailed in the Red Hat advisory RHSA-2026:19455. Patch status is confirmed by the vendor advisory. No additional mitigation steps are indicated.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:19455
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf799f87a2db092a8e14
Added to database: 06/17/2026, 16:46:49 UTC
Last enriched: 06/28/2026, 00:27:09 UTC
Last updated: 07/31/2026, 19:24:46 UTC
Views: 81
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