CIS CYBERSECURITY ADVISORIES

MS-ISAC ADVISORY NUMBER:
2015-046

DATE(S) ISSUED:
04/22/2015

SUBJECT:
Vulnerability in Mozilla Firefox Could Allow for Remote Code Execution

OVERVIEW:

A vulnerability has been identified in Mozilla Firefox, which could allow for remote code execution. Mozilla Firefox is a web browser used to access the Internet. Successful exploitation may allow an attacker to execute arbitrary code in the context of the user running the affected application or result in denial-of-service conditions. Depending on the privileges associated with the user, an attacker could install programs; view, change, or delete data; or create new accounts with full user rights.

THREAT INTELLIGENCE:

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

SYSTEM AFFECTED:

Mozilla Firefox versions prior to 37.0.2

RISK:

Government:

  • Large and medium government entities: High
  • Small government entities: High

Businesses:

  • Large and medium business entities: High
  • Small business entities: High

Home users: High

TECHNICAL SUMMARY:

A use-after-free, memory-corruption vulnerabilityhas been reported in Mozilla Firefox. This vulnerability existsdue to a race condition that occurs when the application fails to properly initialize a plugin. Specifically, this issue occurs due to a crash in the 'AsyncPaintWaitEvent::AsyncPaintWaitEvent(nsIContent*, bool)' function.

This vulnerability can be exploited if a user visits, or is redirected to, a specially crafted web page using the affected program. Successful exploitation of this vulnerability could result in remote code execution, allowing an attacker to run code in the context of the user running the affected application.

RECOMMENDATIONS:

We recommend the following actions be taken:

  • Upgrade to latest versions of Mozilla Firefox after appropriate testing.
  • Run all software as a non-privileged user to diminish effects of a successful attack.
  • Remind users not to click links from unknown sources, or to click links without verifying the intended destination.

REFERENCES:

Mozilla:

https://www.mozilla.org/en-US/security/advisories/mfsa2015-45/

CVE:

http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-2706