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 denial of service via a crafted SASL initial response in the AUTHENTICATE command (CVE-2025-59032), denial of service via a crafted message before authentication (CVE-2026-27858), and denial of service via a specially crafted NOOP command (CVE-2026-27857). These issues affect Red Hat Enterprise Linux 8.6 variants. Red Hat has released security updates addressing these vulnerabilities.
AI Analysis
Technical Summary
This advisory covers three denial of service vulnerabilities in Dovecot. CVE-2025-59032 involves the ManageSieve component 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 8.6 AppStream variants and related update services. Red Hat has issued updated packages (dovecot-2.3.16-2.el8_6.1) to remediate these issues.
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 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 (version 2.3.16-2.el8_6.1) for Red Hat Enterprise Linux 8.6 variants that address these denial of service vulnerabilities. Users should apply these official security updates promptly. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation is specified or required beyond applying the vendor-provided patches.
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 denial of service via a crafted SASL initial response in the AUTHENTICATE command (CVE-2025-59032), denial of service via a crafted message before authentication (CVE-2026-27858), and denial of service via a specially crafted NOOP command (CVE-2026-27857). These issues affect Red Hat Enterprise Linux 8.6 variants. Red Hat has released security updates addressing these vulnerabilities.
Affected software
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 component 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 8.6 AppStream variants and related update services. Red Hat has issued updated packages (dovecot-2.3.16-2.el8_6.1) to remediate these issues.
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 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 (version 2.3.16-2.el8_6.1) for Red Hat Enterprise Linux 8.6 variants that address these denial of service vulnerabilities. Users should apply these official security updates promptly. For update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation is specified or required beyond applying the vendor-provided patches.
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: 06/17/2026, 16:46:49 UTC
Last enriched: 06/28/2026, 00:27:15 UTC
Last updated: 08/01/2026, 19:17:56 UTC
Views: 35
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