A Vulnerability in Mozilla Thunderbird Could Allow for Arbitrary Code Execution

ITS Advisory Number: 
2020-159 - UPDATED
Date(s) Issued: 
Wednesday, December 2, 2020
Date Updated: 
Thursday, December 3, 2020
Subject: 
A Vulnerability in Mozilla Thunderbird Could Allow for Arbitrary Code Execution
Overview: 

A vulnerability has been discovered in Mozilla Thunderbird, which could allow for arbitrary code execution. Mozilla Thunderbird is an email client. Successful exploitation of this vulnerability could allow for arbitrary code execution. Depending on the privileges associated with the user an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.

 

THREAT INTELLIGENCE:

There are no reports of this vulnerability being exploited in the wild.

Systems Affected: 
  • Mozilla Thunderbird versions prior to 78.5.1
RISK
GOVERNMENT
Large and medium government entities: 
High
Small government entities: 
Medium
BUSINESS
Large and medium business entities: 
High
Small business entities: 
Medium
Home Users: 
Low
Description: 

A vulnerability has been discovered in Mozilla Thunderbird, which could allow for arbitrary code execution. This vulnerability exists due incorrect parsing of SMTP server response codes. Depending on processor architecture and stack layout, this leads to stack corruption that may be exploitable. Successful exploitation of this vulnerability could allow for arbitrary code execution. Depending on the privileges associated with the user an attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than those who operate with administrative user rights.

Actions: 
  • After appropriate testing, immediately apply patches provided by Mozilla to vulnerable systems.
  • Run all software as a non-privileged user (one without administrative privileges) to diminish the effects of a successful attack.
  • Remind users not to visit un-trusted websites or follow links provided by unknown or un-trusted sources.
  • Inform and educate users regarding the threats posed by hypertext links contained in emails or attachments especially from un-trusted sources.
  • Apply the Principle of Least Privilege to all systems and services.