Original release date: July 07, 2015

Mozilla has released security updates to address vulnerabilities in Firefox, Firefox ESR, and Thunderbird. Exploitation of one of these vulnerabilities may allow an attacker to take control of an affected system.

Available updates include:

• Firefox 39
• Firefox ESR 38.1
• Thunderbird 38.1

US-CERT encourages users and administrators to review the Security Advisory for Firefox, Firefox ESR, and Thunderbird and apply the necessary updates.

This product is provided subject to this Notification and this Privacy & Use policy.