Apple macOS CVMServer Integer Overflow Privilege Escalation Vulnerability

July 13th, 2021
ZDI-21-794 ZDI-CAN-13345

CVE ID

CVE-2021-30724

CVSS Score

7.8 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Vendors

Apple

Affected Products

macOS

Vulnerability Details

This vulnerability allows local attackers to escalate privileges on affected 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 CVMServer daemon. The issue results from the lack of proper validation of user-supplied data, which can result in an integer overflow before writing to memory. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of root.

Additional Details

 https://support.apple.com/HT212529


Disclosure Timeline

  • 2021-03-17 - Vulnerability reported to vendor
  • 2021-07-13 - Coordinated public release of advisory
  • 2021-07-13 - Advisory Updated

Credit

Mickey Jin (@patch1t) of Trend Micro

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