CVE-2026-74998
CVSS Score
7.2
EPSS Score
0.0%
EPSS Percentile
0th
In Roundcube Webmail before 1.6.18 and 1.7.x before 1.7.3, responses from the CSS (Cascading Style Sheets) proxy were not validated, which may result in information disclosure or XSS (cross-site scripting) via MIME sniffing.
| CWE | CWE-79 |
| Vendor | roundcube |
| Product | webmail |
| Published | Aug 17, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None
Affected Versions
Roundcube / Webmail
1.6.0 < 1.6.18 1.7.0 < 1.7.3
References
roundcube.net: https://roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3 github.com: https://github.com/roundcube/roundcubemail/releases/tag/1.6.18 github.com: https://github.com/roundcube/roundcubemail/commit/62d33c8a0dc3fd0dd03984220dc9709e8e0de43b github.com: https://github.com/roundcube/roundcubemail/releases/tag/1.7.3 github.com: https://github.com/roundcube/roundcubemail/commit/a2334990c02f7cb77b1a8d6fa97fcd9e1b5cd1fb