CVE-2026-35544

An issue was discovered in Roundcube Webmail before 1.5.14 and 1.6.14. Insufficient Cascading Style Sheets (CSS) sanitization in HTML e-mail messages may lead to a fixed-position mitigation bypass via the use of !important.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/roundcube/roundcubemail/commit/099009b9c8e1d3c636fb9a5af72f7c2596018662	Patch
https://github.com/roundcube/roundcubemail/commit/226811a1c974271dbedca72672923abaff8191c0	Patch
https://github.com/roundcube/roundcubemail/commit/57dec0c127b98e0c8e3b9c26c80049b9c4bcaea7	Patch
https://github.com/roundcube/roundcubemail/releases/tag/1.5.14	Release Notes
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)

OR	cpe:2.3:a:roundcube:webmail::::::::
	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-2026-35544

Mitre link : CVE-2026-35544

CVE.ORG link : CVE-2026-35544

JSON object : View

Products Affected

roundcube

webmail

CWE

CWE-669

Incorrect Resource Transfer Between Spheres

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