SB2016082001 - Path traversal and CSRF in wp_ajax_update_plugin() in WordPress WordPress

Description

This security bulletin contains information about 1 security vulnerability.

1) Path traversal and CSRF in wp_ajax_update_plugin() (CVE-ID: CVE-2016-6896)

The vulnerability allows a remote attacker to gain access to potentially sensitive data and cause denial of service.

The vulnerability exists due to insufficient sanitization of directory traversal sequences passed via the "plugin" HTTP GET parameter to wp_ajax_update_plugin() function in "/wp-admin/admin-ajax.php" script. A remote authenticated attacker can send a specially crafted HTTP GET request to vulnerable file and read contents of arbitrary file on the vulnerable system. Additionaly, it is possible to cause denial of service conditions by repeatedly reading /dev/random file and depleting the entropy pool.

This vulnerability can be exploited via CSRF attack, which will allow a remote unauthenticated attacker to cause denial of service of the target system.

Remediation

Install update from vendor's website.

References

• https://sumofpwn.nl/advisory/2016/path_traversal_vulnerability_in_wordpress_core_ajax_handlers.html
• https://codex.wordpress.org/Version_4.6