Description
ManageSieve AUTHENTICATE command crashes when using literal as SASL initial response. This can be used to crash ManageSieve service repeatedly, making it unavailable for other users. Control access to ManageSieve port, or disable the service if it's not needed. Alternatively upgrade to a fixed version. No publicly available exploits are known.
Affected products
dovecot: dovecot; open-xchange: dovecot
References10
- documentation.open-xchange.com/dovecot/security/advisories/csaf… Vendor Advisory
- access.redhat.com/errata/RHSA-2026:13498
- access.redhat.com/errata/RHSA-2026:13830
- access.redhat.com/errata/RHSA-2026:13857
- access.redhat.com/errata/RHSA-2026:17602
- access.redhat.com/errata/RHSA-2026:17625
- access.redhat.com/errata/RHSA-2026:17626
- access.redhat.com/errata/RHSA-2026:17628
- access.redhat.com/errata/RHSA-2026:17630
- access.redhat.com/errata/RHSA-2026:18053
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 55 · as of 12 November 2026
- CWE
- CWE-20CWE-229
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