Description
Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by an improper authentication vulnerability in multi-host installations. When a user logs in with an alias address, rcube_user::query() matched the address against identity records without qualifying the lookup by IMAP host, so a login could be resolved to a user account belonging to a different IMAP host. Upstream fixed this in the commit “Fix bug where an alias login wasn’t qualified by IMAP host”.
Affected products
roundcube: webmail
References6
- github.com/roundcube/roundcubemail/commit/453c413d6851cf603bebd… Patch
- github.com/roundcube/roundcubemail/commit/cb235cbfef88cbf78236d… Patch
- bugs.debian.org/1151279 Third Party AdvisoryMailing List
- github.com/roundcube/roundcubemail/releases/tag/1.6.20 Release Notes
- github.com/roundcube/roundcubemail/releases/tag/1.7.5 Release Notes
- roundcube.net/news/2026/10/19/security-updates-1.6.20-and-1.7.5 Release Notes
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 0% percentile: 33 · as of 8 November 2026
- CWE
- CWE-288
Could this be exploited in your environment?
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