From Brian Krebs:
Oracle Corp. today released an update for its Java SE software that fixes at least 42 security flaws in the widely-installed program and associated browser plugin. The Java update also introduces new features designed to alert users about the security risks of running certain Java content.
Java 7 Update 21 contains 42 new security fixes for Oracle Java SE. A majority of these flaws are browse-to-a-hacked-site-and-get-infected vulnerabilities. According to Oracle, "39 of these vulnerabilities may be remotely exploitable without authentication, i.e., may be exploited over a network without the need for a username and password" [emphasis mine].
Java 7 Update 21 also introduces some new security warnings and message prompts for users who keep the program plugged into a Web browser (on installation and updating, Java adds itself as an active browser plugin). Oracle said the messages that will be presented depend upon different risk factors, such as using old versions of Java or running applet code that is not signed from a trusted Certificate Authority. [Screenshot]
"Apps that present a lower risk display a simple informational message. This includes an option to prevent showing similar messages for apps from the same publisher in the future. Java applications considered to be higher risk — such as those that use an untrusted or expired certificate — will be accompanied by a prompt with a yellow exclamation point in a yellow warning triangle."
⇒ ⇒ I've long urged end users to uninstall Java unless they have a specific use for it (this advice does not scale for businesses, which often have complex custom applications that rely on Java). This widely installed and powerful program is riddled with security holes, and is a favorite target of malware writers and miscreants. Rather than ask users to discern the safety of applications using yellow triangles, blue shields, green clovers or orange stars, I'll keep telling users to get rid of Java entirely.
⇒ ⇒ If you do need it, unplug it from the browser unless and until you need it. Java 7 lets users disable Java content in web browsers through the Java control panel applet. Alternatively, consider a dual-browser approach, unplugging Java from the browser you use for everyday surfing, and leaving it plugged in to a second browser that you only use for sites that require Java.
⇒ ⇒ There are a couple of ways to find out if you have Java installed and what version may be running. Windows users can click Start, then Run, then type "cmd" without the quotes. At the command prompt, type "java -version" (again, no quotes). Users also can visit java.com and click the "Do I have Java?" link on the homepage. Updates also should be available via the Java Control Panel or from Java.com. Mac OS X 10.6 (Snow Leopard) users who have Java should check Software Update for any available updates. Mac OS X 10.7 (Lion) and 10.8 (Mountain Lion) users can grab the updated version of Java from Java.com.
Continued : http://krebsonsecurity.com/2013/04/java-update-plugs-42-security-holes/
Note: Arrows (⇒ ⇒) inserted by me to stress (what I feel to be) important points
From: The Oracle Software Security Assurance Blog
Eric P. Maurice on Apr 16, 2013
Oracle today released two Critical Patch Updates: the April 2013 Critical Patch Update and the April 2013 Critical Patch Update for Java SE. The previous blog entry provided a summary of the April 2013 Critical Patch Update, and this entry will discuss the content of the Critical Patch Update for Java SE.
The April 2013 Critical Patch Update for Java SE provides 42 new security fixes. 39 of the vulnerabilities fixed in this Critical Patch Update are remotely exploitable without authentication. The maximum CVSS Base Score for these vulnerabilities is 10.0, and this score affect 19 different vulnerabilities.
Out of the 42 vulnerabilities, only 2 can affect server deployments of Java. Server exploitation can only occur as a result of these bugs when malicious data is supplied into specific APIs on the server (e.g., through a web service), and one of these bugs actually require local access to be exploited.
As usual, Oracle recommends that this Critical Patch Update be applied as soon as possible. Desktop users can install this new version from java.com or through the Java Autoupdate
For More Information:
The advisory for the April 2013 Critical Patch Update for Java SE is located at http://www.oracle.com/technetwork/topics/security/javacpuapr2013-1928497.html.
⇒ ⇒ NOTE: The offline installer/s can be found here:
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From the SANS ISC: Java 7 Update 21 is available - Watch for Behaviour Changes !
Several of our readers have written in to let us know about the latest Java Update.
So why isn't this a normal one-liner with a pointer off to the readme? Because Oracle has significantly changed how Java runs with this version. Java now requires code signing, and will pop up brightly coloured dialogue boxes if your code is not signed. They now alert on unsigned, signed-but-expired and self-signed certificates.
We'll even need to click "OK" when we try to download and execute signed and trusted Java.
This is a really positive move on their part - with as many problems as Java has, it'll be nice to stop blaming the developers of the language entirely for malicious code - Java doesn't give you malware, running malware gives you malware.
(not that Java is perfect, mind you)
The graphics you can expect to see once you update are:
[Screenshot: Valid Certificate] - [Screenshot: Self-Signed Certificate]
[Screenshot:Expired Certificate] - [Screenshot: Unsigned Application]
Full details on the new run policy can be found here ==> https://www.java.com/en/download/help/appsecuritydialogs.xml
And more information can be found here ==> http://www.oracle.com/technetwork/java/javase/tech/java-code-signing-1915323.html