Multiple Vulnerabilities in Apple iOS Could Allow for Arbitrary Code Execution

ITS Advisory Number: 
2021-081
Date(s) Issued: 
Tuesday, June 15, 2021
Subject: 
Multiple Vulnerabilities in Apple iOS Could Allow for Arbitrary Code Execution
Overview: 

Multiple vulnerabilities have been discovered in Apple iOS that could allow for arbitrary code execution. iOS is a mobile operating system for mobile devices, including the iPhone, iPad, and iPod touch. Successful exploitation of these vulnerabilities could result in arbitrary code execution within the context of the application, an attacker gaining the same privileges as the logged-on user, or the bypassing of security restrictions. Depending on the permission associated with the application running the exploit, an attacker could then install programs; view, change, or delete data.

 

THREAT INTELLIGENCE:

Apple is aware that CVE-2021-30761 and CVE-2021-30762 may have been actively exploited.

 

Systems Affected: 
  • iOS versions prior to 12.5.4
RISK
GOVERNMENT
Large and medium government entities: 
High
Small government entities: 
High
BUSINESS
Large and medium business entities: 
High
Small business entities: 
High
Home Users: 
Low
Description: 

Multiple vulnerabilities have been discovered in Apple iOS that could allow for arbitrary code execution. Details of these vulnerabilities are as follows:

 

  • A memory corruption issue in the ASN.1 decoder may lead to arbitrary code execution. (CVE-2021-30737)
  • A memory corruption issue in WebKit may lead to arbitrary code execution. (CVE-2021-30761)
  • A use after free issue in WebKit may lead to arbitrary code execution. (CVE-2021-30762)

 

Successful exploitation of these vulnerabilities could result in arbitrary code execution within the context of the application, an attacker gaining the same privileges as the logged-on user, or the bypassing of security restrictions. Depending on the permission associated with the application running the exploit, an attacker could then install programs; view, change, or delete data.

 

Actions: 
  • After appropriate testing, immediately apply patched provided by Apple to vulnerable systems.
  • Run all software as a nonprivileged user (one without administrative privileges) to diminish the effects of a successful attack.
  • Remind users not to download, accept or execute files from untrusted and unknown sources.
  • Remind users not to visit untrusted websites or follow links provided by untrusted or unknown sources.
  • Evaluate read, write, and execute permissions on all newly installed software
  • Apply the Principle of Least Privilege to all systems and services.