Description
Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a mail header injection vulnerability in the Bounce (resend) action. rcube_mime::decode_address_list() did not strip control characters from the decoded display name, so a received message whose From display-name carries CRLF sequences in an encoded word could inject arbitrary headers into the message emitted when the user bounces it. Upstream fixed this in the commit “Fix mail header injection via the From display-name in the Bounce (resend) action”.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Roundcube | Webmail | 1.6.0 – < 1.6.20, 1.7.0 – < 1.7.5 | 1.6.20 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | roundcube | 1.6.20+dfsg-1 | — |
| Debian 13 | roundcube | 1.6.20+dfsg-0+deb13u1 | — |
| Debian 12 | roundcube | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | roundcube | No fix yet | — |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | roundcube | No fix yet | — |
| Ubuntu Pro 24.04 LTS | roundcube | No fix yet | — |
| Ubuntu Pro 22.04 LTS | roundcube | No fix yet | — |
| Ubuntu Pro 20.04 LTS | roundcube | No fix yet | — |
| Ubuntu Pro 18.04 LTS | roundcube | No fix yet | — |
| Ubuntu Pro 16.04 LTS | roundcube | No fix yet | — |
Advisories 1
- WID-SEC-2026-4043 Roundcube Webmail: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 5, 2026
References
- https://bugs.debian.org/1151279 issue-tracking third-party-advisory
- https://github.com/roundcube/roundcubemail/commit/d3a35545fdaf72b02a9a4d670064895488e9d9d0 patch
- https://roundcube.net/news/2026/10/19/security-updates-1.6.20-and-1.7.5 vendor-advisory release-notes
- https://github.com/roundcube/roundcubemail/releases/tag/1.7.5 release-notes patch
- https://github.com/roundcube/roundcubemail/releases/tag/1.6.20 release-notes patch
- https://github.com/roundcube/roundcubemail/commit/3a136465c965776a5f636587187626985dae4f3b patch