Summary

• A vulnerability in the Chakra scripting engine used by Microsoft Edge could allow an unauthenticated, remote attacker to execute arbitrary code on a targeted system.
  
  The vulnerability is due to improper memory operations that are performed by the affected software. An attacker could exploit the vulnerability by persuading a user to access a link or file that submits malicious input to the affected software. A successful exploit could allow the attacker to execute arbitrary code with the privileges of the user. If the user has elevated privileges, the attacker could compromise the system completely.
  
  Microsoft confirmed the vulnerability and released software updates.

Analysis

• To exploit this vulnerability, the attacker may use misleading language or instructions to persuade a user to access a file that submits malicious input to the affected software.
  
  Although the CVSS score indicates low impact to confidentiality and integrity, a successful exploit could allow the attacker to execute arbitrary code in the security context of the current user. If the user has elevated privileges, a successful exploit could result in a complete system compromise.
  
  Microsoft addressed this vulnerability by changing how the affected software handles objects in memory.

Safeguards

• Administrators are advised to apply the appropriate updates.
  
  Administrators are advised to allow only trusted users to have network access.
  
  Users are advised not to open email messages from suspicious or unrecognized sources. If users cannot verify that links or attachments included in email messages are safe, they are advised not to open them.
  
  Users are advised not to visit websites or follow links that have suspicious characteristics or cannot be verified as safe.
  
  Administrators may consider using the Microsoft Baseline Security Analyzer (MBSA) scan tool to identify common security misconfigurations and missing security updates on system endpoints.
  
  Administrators are advised to use an unprivileged account when browsing the Internet.
  
  Administrators are advised to monitor critical systems.

Vendor Announcements

• Microsoft has released detailed information at the following link: Security Update Guide

Fixed Software

• Microsoft customers can obtain updates directly by using the links in the Microsoft Security Update Guide. These updates are also distributed by Windows automatic update features and are available from the Microsoft Update Catalog. Microsoft Windows Server Update Services (WSUS), Systems Management Server, and System Center Configuration Manager can assist administrators in deploying software updates.

Revision History

• Version	Description	Section	Date
  1	Initial public release.	—	May-07-2018

  Show Less

Affected Products

• The security vulnerability applies to the following combinations of products.
  
  

  Primary Products
  Microsoft, Inc.	ChakraCore	1.6.2 (Base)

  Associated Products