SB2020083113 - Cross-site scripting in Subscribe Sidebar plugin by Blubrry for WordPress

Description

This security bulletin contains information about 1 security vulnerability.

1) Cross-site scripting (CVE-ID: CVE-2020-25033)

The disclosed 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 "status" GET parameter in "subscribe_sidebar.php" file. A remote authenticated attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

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.

PoC:

/wp-admin/options-general.php?page=subscribe_sidebar.php&status=%3Cscript%3Ealert%28document.cookie%29%3C%2Fscript%3E

Remediation

Cybersecurity Help is not aware of any official remediation provided by the vendor.

References

• https://wordpress.org/plugins/subscribe-sidebar/#developers
• https://zeroaptitude.com/pitticus/subscribe-sidebar-plugin-by-blubrry-v1-3-1-reflected-xss-20-jun-2020/