Oracle Java 7 Security Manager Bypass Vulnerability

Any system using Oracle Java 7 (1.7, 1.7.0) including

• Java Platform Standard Edition 7 (Java SE 7)
• Java SE Development Kit (JDK 7)
• Java SE Runtime Environment (JRE 7)
• OpenJDK 7 and 7u
• IcedTea 2.x (IcedTea7 2.x)

All versions of Java 7 through update 10 are affected.  Web browsers using the Java 7 plug-in are at high risk.

A vulnerability in the way Java 7 restricts the permissions of Java applets could allow an attacker to execute arbitrary commands on a vulnerable system.

A vulnerability in the Java Security Manager allows a Java applet to grant itself permission to execute arbitrary code. An attacker could use social engineering techniques to entice a user to visit a link to a website hosting a malicious Java applet. An attacker could also compromise a legitimate web site and upload a malicious Java applet (a "drive-by download" attack).

Any web browser using the Java 7 plug-in is affected. The Java Deployment Toolkit plug-in and Java Web Start can also be used as attack vectors.

Reports indicate this vulnerability is being actively exploited, and exploit code is publicly available.

Further technical details are available in Vulnerability Note VU#625617.

By convincing a user to load a malicious Java applet or Java Network Launching Protocol (JNLP) file, an attacker could execute arbitrary code on a vulnerable system with the privileges of the Java plug-in process.

Update Java

Oracle Security Alert CVE-2013-0422 states that Java 7 Update 11 (7u11) addresses this (CVE-2013-0422) and a different but equally severe vulnerability (CVE-2012-3174).

Java 7 Update 11 sets the default Java security settings to "High" so that users will be prompted before running unsigned or self-signed Java applets.

Disable Java in web browsers

This and previous Java vulnerabilities have been widely targeted by attackers, and new Java vulnerabilities are likely to be discovered. To defend against this and future Java vulnerabilities, consider disabling Java in web browsers until adequate updates are available. As with any software, unnecessary features should be disabled or removed as appropriate for your environment.

Starting with Java 7 Update 10, it is possible to disable Java content in web browsers through the Java control panel applet. From Setting the Security Level of the Java Client:

For installations where the highest level of security is required, it is possible to entirely prevent any Java apps (signed or unsigned) from running in a browser by de-selecting Enable Java content in the browser in the Java Control Panel under the Security tab.

If you are unable to update to Java 7 Update 10 please see the solution section of Vulnerability Note VU#636312 for instructions on how to disable Java on a per-browser basis.Vulnerability Note VU#625617

January 10, 2013: Initial release|January 14, 2013: Added fix information per Java 7u11 release|January 15, 2013: Added OpenJDK and IcedTea to Systems Affected