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.
History

Mon, 17 Aug 2026 15:15:00 +0000

Type Values Removed Values Added
Title Unvalidated CSS Proxy Response Causing XSS and Information Disclosure in Roundcube Webmail

Mon, 17 Aug 2026 13:00:00 +0000

Type Values Removed Values Added
Description 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.
First Time appeared Roundcube
Roundcube webmail
Weaknesses CWE-79
CPEs cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:*
Vendors & Products Roundcube
Roundcube webmail
References
Metrics cvssV3_1

{'score': 7.2, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-08-17T16:01:16.269Z

Reserved: 2026-08-17T12:40:29.556Z

Link: CVE-2026-74998

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-08-17T13:16:54.270

Modified: 2026-08-17T16:17:51.297

Link: CVE-2026-74998

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-17T15:00:08Z