Description
Roundcube Webmail 1.6.x between 1.6.14 and 1.6.16,and 1.7.x before 1.7.1 has Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to SSRF or Information Disclosure, e.g., if stylesheet links point to local network hosts. The issue stems from an insufficient fix for CVE-2026-35540.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Roundcube | Webmail | 1.6.14 – < 1.6.16, 1.7.0 – < 1.7.1 | 1.6.16 |
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 | 1.6.16+dfsg-1 | — |
| Debian 13 | roundcube | 1.6.16+dfsg-0+deb13u1 | — |
| Debian 12 | roundcube | 1.6.5+dfsg-1+deb12u9 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | roundcube | No fix yet | — |
| Ubuntu 25.10 | 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 | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | roundcubemail | 1.6.16-2.1 | openSUSE-SU-2026:10869-1 |
Advisories 2
- WID-SEC-2026-1671 Roundcube Webmail: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 5, 2026
- openSUSE-SU-2026:10869-1 roundcubemail-1.6.16-2.1 on GA media SUSE / openSUSE Security Updates · May 28, 2026
References
- https://roundcube.net/news/2026/05/24/security-updates-1.6.16-and-1.7.1
- https://github.com/roundcube/roundcubemail/releases/tag/1.7.1
- https://github.com/roundcube/roundcubemail/commit/ab96c88bfd888866ec5e02190b19618db283923a
- https://github.com/roundcube/roundcubemail/releases/tag/1.6.16
- https://github.com/roundcube/roundcubemail/commit/cb3fc9041e91640ba9ba49ee7b2147c176ebf5a1