Cross-site scripting in Roundcube Webmail

1) Cross-site scripting

EUVDB-ID: #VU50432

Risk: Medium

CVSSv3.1: 6.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-26925

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied CSS content passed via HTML messages. A remote attacker can send a specially crafted email message to the victim and execute arbitrary HTML and script code in user's browser in context of vulnerable website, once the malicious email is opened.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Roundcube: 1.4.0 - 1.4.10

External links

http://github.com/roundcube/roundcubemail/commit/9f19b931e3b89c2fa577e2bf719f7db84492eb66
http://github.com/roundcube/roundcubemail/releases/tag/1.4.11

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.