Vulnerability · Published Oct 22, 2026 · Assigned by mitre
CVE-2026-114722
Medium 6.5
In plain English
A medium-severity security flaw in Webmail from Roundcube. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 is affected by a CSS scoping bypass in HTML messages. rcube_utils::mod_css_styles() did not treat an at-rule prologue such as @layer a; as a selector boundary, and did not handle selectors beginning with ::, so selectors following an at-rule were left unscoped and applied to the whole Roundcube interface instead of being confined to the message body. This allows an HTML message to restyle application chrome for UI redressing and spoofing. Upstream fixed this in the commit “Fix CSS scoping bypass in HTML messages using at-rules”.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | roundcube | no fix listed | DEBIAN-CVE-2026-114722 |
| Debian:13 | roundcube | 1.6.20+dfsg-0+deb13u1 | DEBIAN-CVE-2026-114722 |
| Debian:14 | roundcube | 1.6.20+dfsg-1 | DEBIAN-CVE-2026-114722 |
| Ubuntu:26.10 | roundcube | no fix listed | UBUNTU-CVE-2026-114722 |
Affected products (as reported)
Weakness: CWE-669 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
References
- https://bugs.debian.org/1151279 issue-tracking, third-party-advisory
- https://github.com/roundcube/roundcubemail/commit/95b81ae12e2819a9b7e8636b5859b6244cda383e 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/ff9cf4a9bf3b7c66db9afe43fe5f1cc73b47ed35 patch