Name: CVE-2026-35540: Incorrect Resource Transfer Between Spheres
Creator: Rapid7
Published: 2026-04-03T00:00:00.000Z
License: https://www.rapid7.com/legal/website-terms-of-use/
Keywords: CVE, CVE-2026-35540, CWE-669, CVSS 6.5, EPSS 0.00386

An issue was discovered in Roundcube Webmail 1.6.0 before 1.6.14. 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.

CVSS Details

CVSS 3.1 Base Score: 6.5
CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N)

Covered by Rapid7

Product	Vendor Advisory	Solution File	Added	Published
Debian	—	Upgrade roundcube	Apr 6, 2026	Apr 6, 2026

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CVSS Details

Covered by Rapid7

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