CVE-2026-35540

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 v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/roundcube/roundcubemail/commit/27ec6cc9cb25e1ef8b4d4ef39ce76d619caa6870	Patch
https://github.com/roundcube/roundcubemail/commit/579b68eff90650a5c782e153debd66c765648942	Patch
https://github.com/roundcube/roundcubemail/releases/tag/1.6.14	Release Notes
https://github.com/roundcube/roundcubemail/releases/tag/1.7-rc5	Release Notes
https://roundcube.net/news/2026/03/18/security-updates-1.7-rc5-1.6.14-1.5.14	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:roundcube:webmail:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-04-03 05:16

Updated : 2026-07-24 21:10

NVD link : CVE-2026-35540

Mitre link : CVE-2026-35540

CVE.ORG link : CVE-2026-35540

JSON object : View

Products Affected

roundcube

webmail

CWE

CWE-669

Incorrect Resource Transfer Between Spheres

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