SB2019050701 - Multiple vulnerabilities in W3 Total Cache plugin for WordPress
Published: May 7, 2019
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 secuirty vulnerabilities.
1) Input validation error (CVE-ID: N/A)
The vulnerability allows a remote attacker to bypass certain security restrictions.
The vulnerability exists due to insufficient validation of "openssl_verify" result in "/services/MessageValidator/MessageValidator.php". A remote attacker can create a specially crafted certificate and bypass cryptographic check.
2) Server-Side Request Forgery (SSRF) (CVE-ID: N/A)
The disclosed vulnerability allows a remote attacker to perform SSRF attacks.
The vulnerability exists due to insufficient validation of user-supplied input in the opcache_flush_file() function that calls file_exists() function on attacker-controlled data. A remote attacker can send a specially crafted HTTP request to the "/wp-content/plugins/w3-total-cache/pub/opcache.php" URL and trick the application to initiate requests to arbitrary systems.
Successful exploitation of this vulnerability may allow a remote attacker gain access to sensitive data, located in the local network or send malicious requests to other servers from the vulnerable system.
Example:
curl 'http://[host]/wp-content/plugins/w3-total-cache/pub/opcache.php' --data 'nonce=974ca6ad15021a6668e7ae02e1be551c&command=flush_file&file=[TARGET_URL]'
3) Cross-site scripting (CVE-ID: N/A)
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 "command" HTTP POST parameter to "/wp-content/plugins/w3-total-cache/pub/opcache.php" script. A remote 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.
Remediation
Install update from vendor's website.