TippingPoint Zero Day Initiative

Apple OS X iCloud Account Authentication Elevation Of Privilege Vulnerability

ZDI-15-390: August 13th, 2015


CVSS Score

Affected Vendors

Affected Products

Vulnerability Details

This vulnerability allows attackers to execute arbitrary code on vulnerable installations of Apple OS X. An attacker must have shell access to exploit this vulnerability, however Guest access is sufficient.

The specific flaw exists within the authentication of users who use their iCloud account and password to log in to OS X. Any user is able to change the password of these users without knowing the previous password. This allows an attacker to run arbitrary commands as that user. If the target user is an Admin, the attacker can run arbitrary commands as root.

Vendor Response

Apple has issued an update to correct this vulnerability. More details can be found at:

Disclosure Timeline

    2015-06-10 - Vulnerability reported to vendor
    2015-08-13 - Coordinated public release of advisory


This vulnerability was discovered by: