Description
Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a mail header injection vulnerability when a message is forwarded as an attachment. The subject of the forwarded message was used verbatim to generate the attachment name, so a received message whose subject contains CRLF sequences could inject arbitrary MIME part headers into the outgoing message. Upstream fixed this in the commit “Fix mail header injection via subject of a message forwarded as attachment”, which collapses whitespace in the generated name.
Affected products
roundcube: webmail
References6
- github.com/roundcube/roundcubemail/commit/4c3291ce9df9e1d3b4533… Patch
- github.com/roundcube/roundcubemail/commit/c325953a251d0132f1909… 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 Issue Tracking
Metrics
- CVSS 3.1
-
5.8
MEDIUM
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N - EPSS — exploit probability
- 0% percentile: 39 · as of 8 November 2026
- CWE
- CWE-99
Could this be exploited in your environment?
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