Stored XSS in WP Live Chat Support for WordPress

1) Stored cross-site scripting

EUVDB-ID: #VU18517

Risk: Medium

CVSSv3.1: 5.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:P/RL:O/RC:C]

CVE-ID: CVE-2018-9864

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

Exploit availability: No

Description

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

The vulnerability exists due to insufficient sanitization of user-supplied data passed via the Name field. A remote attacker can permanently store and execute arbitrary HTML and script code in user's browser in context of vulnerable website, when chat history is viewed by website administrators.

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 update from vendor's website.

Vulnerable software versions

WP Live Chat Support: 1.0 - 8.0.05

External links

http://wordpress.org/plugins/wp-live-chat-support/#developers
http://www.gubello.me/blog/wp-live-chat-support-8-0-05-stored-xss/
http://www.youtube.com/watch?v=eHG1pWaez9w

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. However, proof of concept for this vulnerability is available.