Multiple Vulnerabilities in Mozilla Thunderbird Could Allow for Arbitrary Code Execution

ITS Advisory Number: 
2018-071
Date(s) Issued: 
Friday, July 6, 2018
Subject: 
Multiple Vulnerabilities in Mozilla Thunderbird Could Allow for Arbitrary Code Execution
Overview: 

Multiple vulnerabilities have been discovered in Mozilla Thunderbird, the most severe of which could allow for arbitrary code execution. Mozilla Thunderbird is an email client. Successful exploitation of the most severe of these vulnerabilities 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:

Proof of concept code is available for CVE-2018-12372 and CVE-2018-12373.

Systems Affected: 
  • Mozilla Thunderbird versions prior to 52.9

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: 

Multiple vulnerabilities have been identified in Mozilla Thunderbird, the most severe of which could allow for arbitrary code execution. Details of the vulnerabilities are as follows:

 

  • A buffer overflow can occur when rendering canvas content while adjusting the height and width of the <canvas> element dynamically, causing data to be written outside of the currently computed boundaries. This results in a potentially exploitable crash. (CVE-2018-12359)

  • A compromised IPC child process can escape the content sandbox and list the names of arbitrary files on the file system without user consent or interaction. This could result in exposure of private local files. (CVE-2018-12365)

  • An integer overflow can occur during graphics operations done by the Supplemental Streaming SIMD Extensions 3 (SSSE3) scaler, resulting in a potentially exploitable crash. (CVE-2018-12362)

  • An invalid grid size during QCMS (color profile) transformations can result in the out-of-bounds read interpreted as a float value. This could leak private data into the output. (CVE-2018-12366)

  • A use-after-free vulnerability can occur when deleting an input element during a mutation event handler triggered by focusing that element. This results in a potentially exploitable crash. (CVE-2018-12360)

  • A use-after-free vulnerability can occur when script uses mutation events to move DOM nodes between documents, resulting in the old document that held the node being freed but the node still having a pointer referencing it. This results in a potentially exploitable crash. (CVE-2018-12363)

  • Decrypted S/MIME parts hidden with CSS or <plaintext> can leak plaintext when included in a HTML reply/forward. (CVE-2018-12373)

  • Decrypted S/MIME parts, when included in HTML crafted for an attack, can leak plaintext when included in a HTML reply/forward. (CVE-2018-12372)

  • Memory safety bugs present, with some of the bugs showing evidence of memory corruption and could potentially be exploited to run arbitrary code. (CVE-2018-5188)

  • NPAPI plugins, such as Adobe Flash, can send non-simple cross-origin requests, bypassing CORS by making a same-origin POST that does a 307 redirect to the target site. This allows for a malicious site to engage in cross-site request forgery (CSRF) attacks. (CVE-2018-12364)

  • Plaintext of decrypted emails can leak through by user submitting an embedded form by pressing enter key within a text input field. (CVE-2018-12374)

  • Windows 10 does not warn users before opening executable files with the SettingContent-ms extension even when they have been downloaded from the internet and have the "Mark of the Web." Without the warning, unsuspecting users unfamiliar with this new file type might run an unwanted executable. This also allows a WebExtension with the limited downloads.open permission to execute arbitrary code without user interaction on Windows 10 systems. Note: this issue only affects Windows operating systems. Other operating systems are unaffected. (CVE-2018-1236) 

Successful exploitation of the most severe of these vulnerabilities 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 updates 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.