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). Red Hat has issued an important security advisory with updates addressing these issues for Red Hat Enterprise Linux 9.4 and related variants.
AI Analysis
Technical Summary
Dovecot contains three denial of service vulnerabilities: CVE-2025-59032 allows denial of service through a crafted SASL initial response in the AUTHENTICATE command of ManageSieve; CVE-2026-27858 allows denial of service via a crafted message sent before authentication; and CVE-2026-27857 allows denial of service via a specially crafted NOOP command. These vulnerabilities affect Red Hat Enterprise Linux 9.4 and related distributions. Red Hat has released updated packages to remediate these issues as detailed in advisory RHSA-2026:17625.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email access for users. 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 for Red Hat Enterprise Linux 9.4 and related variants that address these denial of service vulnerabilities. Users should apply the security updates as described in Red Hat advisory RHSA-2026:17625 and the referenced article https://access.redhat.com/articles/11258. No additional mitigations are specified 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 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). Red Hat has issued an important security advisory with updates addressing these issues for Red Hat Enterprise Linux 9.4 and related variants.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
Dovecot contains three denial of service vulnerabilities: CVE-2025-59032 allows denial of service through a crafted SASL initial response in the AUTHENTICATE command of ManageSieve; CVE-2026-27858 allows denial of service via a crafted message sent before authentication; and CVE-2026-27857 allows denial of service via a specially crafted NOOP command. These vulnerabilities affect Red Hat Enterprise Linux 9.4 and related distributions. Red Hat has released updated packages to remediate these issues as detailed in advisory RHSA-2026:17625.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service conditions in the Dovecot service, potentially disrupting email access for users. 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 for Red Hat Enterprise Linux 9.4 and related variants that address these denial of service vulnerabilities. Users should apply the security updates as described in Red Hat advisory RHSA-2026:17625 and the referenced article https://access.redhat.com/articles/11258. No additional mitigations are specified 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-2026:17625
- Cve Count
- 3
- Additional Cves
- ["CVE-2026-27857","CVE-2026-27858"]
- Cvss Version
- null
Threat ID: 6a32cf7e9f87a2db092a946c
Added to database: 6/17/2026, 4:46:54 PM
Last enriched: 6/17/2026, 4:51:04 PM
Last updated: 6/17/2026, 6:23:14 PM
Views: 2
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