Advisory Details

May 15th, 2017

(Pwn2Own) Apple macOS speechsynthesisd Unsigned Dylib Loading Privilege Escalation Vulnerability

ZDI-17-347
ZDI-CAN-4581

CVE ID CVE-2017-2534, CVE-2017-6977
CVSS SCORE 4.6, AV:L/AC:L/Au:N/C:P/I:P/A:P
AFFECTED VENDORS Apple
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 speechsynthesisd service. The issue results from the lack of proper validation of a library prior to loading it. An attacker can leverage this vulnerability to escalate privileges under the context of the current service.
ADDITIONAL DETAILS Apple has issued an update to correct this vulnerability. More details can be found at:
https://support.apple.com/en-us/HT207797
DISCLOSURE TIMELINE
  • 2017-03-15 - Vulnerability reported to vendor
  • 2017-05-15 - Coordinated public release of advisory
CREDIT Niklas Baumstark and Samuel Groß
BACK TO ADVISORIES