Red Hat Security Advisory: dovecot security update
Multiple denial of service vulnerabilities have been identified in Dovecot, an IMAP and POP3 server for UNIX-like systems. These include issues in the ManageSieve plugin via a crafted SASL initial response during the AUTHENTICATE command, denial of service via a crafted message before authentication, and denial of service via a specially crafted NOOP command. Red Hat has released security updates addressing these vulnerabilities in Red Hat Enterprise Linux 9 and related variants.
AI Analysis
Technical Summary
This advisory covers three denial of service vulnerabilities in Dovecot: CVE-2025-59032 affects the ManageSieve plugin allowing denial of service via a crafted SASL initial response in the AUTHENTICATE command. CVE-2026-27858 allows denial of service via a crafted message before authentication. CVE-2026-27857 allows denial of service via a specially crafted NOOP command. Red Hat has issued updates for Red Hat Enterprise Linux 9 and its extended support versions 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 impacts. 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 and its extended support variants that address these vulnerabilities. Users should apply these official patches as detailed in the Red Hat advisory RHSA-2026:13857. Patch status is confirmed as fixed in these updated packages. No additional mitigation steps are indicated by the vendor.
Red Hat Security Advisory: dovecot security update
Description
Multiple denial of service vulnerabilities have been identified in Dovecot, an IMAP and POP3 server for UNIX-like systems. These include issues in the ManageSieve plugin via a crafted SASL initial response during the AUTHENTICATE command, denial of service via a crafted message before authentication, and denial of service via a specially crafted NOOP command. Red Hat has released security updates addressing these vulnerabilities in Red Hat Enterprise Linux 9 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 affects the ManageSieve plugin allowing denial of service via a crafted SASL initial response in the AUTHENTICATE command. CVE-2026-27858 allows denial of service via a crafted message before authentication. CVE-2026-27857 allows denial of service via a specially crafted NOOP command. Red Hat has issued updates for Red Hat Enterprise Linux 9 and its extended support versions 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 impacts. 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 and its extended support variants that address these vulnerabilities. Users should apply these official patches as detailed in the Red Hat advisory RHSA-2026:13857. Patch status is confirmed as fixed in these updated packages. No additional mitigation steps are indicated by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:13857
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a947f
Added to database: 6/17/2026, 4:46:54 PM
Last enriched: 6/17/2026, 4:50:50 PM
Last updated: 6/17/2026, 6:23:13 PM
Views: 3
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