CVE-2026-74998

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.

CVSS v3 7.2 HIGH

7.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

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/62d33c8a0dc3fd0dd03984220dc9709e8e0de43b	Patch
https://github.com/roundcube/roundcubemail/commit/a2334990c02f7cb77b1a8d6fa97fcd9e1b5cd1fb	Patch
https://github.com/roundcube/roundcubemail/releases/tag/1.6.18	Release Notes
https://github.com/roundcube/roundcubemail/releases/tag/1.7.3	Release Notes
https://roundcube.net/news/2026/08/09/security-updates-1.6.18-and-1.7.3	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:roundcube:webmail::::::::
	cpe:2.3:a:roundcube:webmail::::::::

History

No history.

Information

Published : 2026-08-17 13:16

Updated : 2026-09-08 19:10

NVD link : CVE-2026-74998

Mitre link : CVE-2026-74998

CVE.ORG link : CVE-2026-74998

JSON object : View

Products Affected

roundcube

webmail

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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