TippingPoint Zero Day Initiative
 

(Pwn2Own) Apple macOS WindowServer _XGetWindowMovementGroup Stack-based Buffer Overflow Privilege Escalation Vulnerability

ZDI-17-349: May 15th, 2017

CVE ID

CVSS Score

Affected Vendors

Affected Products

    macOS

Vulnerability Details


This vulnerability allows local attackers to escalate privileges on vulnerable installations of Apple macOS. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.

The specific flaw exists within the WindowServer process. The issue results from the lack of proper validation of the length of user-supplied data prior to copying it to a stack-based buffer. An attacker can leverage this vulnerability to escalate privileges under the context of the WindowServer.

Vendor Response

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

Disclosure Timeline

    2017-03-15 - Vulnerability reported to vendor
    2017-05-15 - Coordinated public release of advisory

Credit

This vulnerability was discovered by:
    Richard Zhu (fluorescence)