Java 8 Update 40 Installer App Fun!

So perhaps you saw my previous post: Java 8 without the Adware (aka Java8Unjunker)?

Java 8 U40 App

Good stuff eh? There was something in there that got me thinking: If they didn’t sign the package, is the app doing any integrity checks on the package inside either? Hmmm let’s see…

Voice over: We’ve secretly replaced the JavaAppletPlugin.pkg package with QuickTime 7 let’s see if it can tell the difference!
Not Java

Here we go!
Sure let me authenticate right when you run before any confirmation of action – why not!? (Ugh, bad form already.)

Java8 Auth

Safe and Easy

Oh OK, “safe and easy” – I love it! But just to clarify…
By “easy” you mean: Checking lots of trust boxes and clicking “Run” buttons a lot to get a Java apps working (plus crossing your fingers)?
By “safe” you mean: a steady stream of high scored CVEs with low complexity? Or even running in Unsafe Mode when needed?

OK what’s next?

Ask

Oh dear God no! No Ask.com. UncheckNext.

Oh, right, away we go, I gave you my password at the door. Installing Java are we?
Java8 InstallingInstalled

OK I’ve successfully installed Java then if you say so… I guess I that’s proof alright!
It then takes you to the Verify Java page — but who cares about that!

What does /var/log/install.log say about what was installed?

QT7 install Java8

 

Yep it installed the QuickTime7 package we put in there and Java Updater 40.app was none the wiser.

So in conclusion… That’s a really nifty “Ask Toolbar installer” with arbitrary package installer Oracle. It’s also a great delivery vehicle for malware by nefarious folks. Heck, bundle Java along with your Trojan and the “Verify Java” page would open too! Sheesh. Is the Ask contract that lucrative? Oracle made $38 billion in revenue last year, IAC the parent of Ask.com pulled in $3 billion. I guess IAC have got money to spend and Oracle will take it (but not invest in more secure installers?)

Notes: The first attempt used a QuickTimePlayer7.6.6_SnowLeopard.pkg with an expired certificate, that halted the install. The 2nd attempt I stripped out the expired certificate. It worked. The 3rd time I downloaded a newly signed version from Apple, that too worked.

Parting note for Oracle:
Sign your critical packages! If you insist on using your glorified “Ask Toolbar installer app” to do this, then require that it verify the package integrity in some way, Orable! (heh, that was a typo but I like it: Orable, ha!)

Open JavaAppletPluginJava8 No Lock

 

Update: Oracle is now signing the package within and the installer can no longer be duped into running an arbitrary package. The version when this article was written was 1.8.40.25, it is now 1.8.40.27.

Java 8 Signed

It’s signed now!

 

Damaged Java 8

Attempted JavaAppletPlugin.pkg Replacement

 

Java 8 without the Adware (aka Java8Unjunker)

So you’ve heard the Ask toolbar is now bundled with Java 8 Update 40 for the Mac?
Yep, apparently it is.

Ask

Fortunately there’s a simple workaround! Let’s take control of our Macs and do a little spelunking into this new installer app.

Right or Control-Click the Java 8 Update xx.app and choose Show Package Contents

Show Package Contents

Navigate into Contents then Resources folder
Eureka we’ve found it: JavaAppletPlugin.pkg
JavaAppletPlugin_LocationLet’s run it!

Gatekeeper_Java8

Aw snap. It seems the package isn’t signed and Gatekeeper is not happy about that. I’m flabbergasted that they’d sign the installer app but not the package inside? (Update: I’m really flabbergasted!)

Control or right-click on JavaAppletPlugin.pkg and choose Open

Java 8 PKG Open

Click Open

Open JavaAppletPlugin

Here we are. Your unsigned Java installer awaits.

Installer

Alternately… Java8Unjunker.command

script I just made to do the same thing plus some other nice things like: name the package and un-quarantine it. Of course being a script it’s not signable! Gatekeeper will balk if it’s on. You’ll need to right-click and choose Open as before.

Shell

Drag in your Java 8 Updater xx.app

Unjunker1

Press Enter.
Voilà! A folder with your package ready to double-click and go.

Unjunker2

Enjoy.

TMI…

#!/bin/bash

#Java 8 Unjunker - Joel Bruner
#Simply moves the JavaAppletPlugin.pkg package out of the installer app (which installs the Ask Toolbar) to the Desktop, renames and Un-Quarantines it

#touch file for debugging
[ -f /tmp/debug ] && set -x

#take command line argument too
sourceApp="$1"

#check to see if path provided is present and valid
#otherwise get the path
while [ -z "$sourceApp" -o ! -d "$sourceApp" ]; do
echo -n "Drag in Java 8 Update xx.app and press enter: "
read sourceApp
done

#get the version from the app
sourcePKGVersion=$(defaults read "$sourceApp"/Contents/Info CFBundleVersion)

#make Desktop folder and copy pkg to it, renamed
echo "Creating Directory ~/Desktop/Java $sourcePKGVersion"
mkdir ~/Desktop/"Java $sourcePKGVersion"
echo "Copying JavaAppletPlugin.pkg to ~/Desktop/Java $sourcePKGVersion/JavaAppletPlugin_${sourcePKGVersion}.pkg"
cp "$sourceApp"/Contents/Resources/JavaAppletPlugin.pkg ~/Desktop/"Java $sourcePKGVersion"/JavaAppletPlugin_${sourcePKGVersion}.pkg

#since Oracle doesn't sign the pkg just the .app we need to strip the quarantine xa off to suppress the warning
xattr -d com.apple.quarantine ~/Desktop/"Java $sourcePKGVersion"/JavaAppletPlugin_${sourcePKGVersion}.pkg

echo "Java Unjunked. Opening Folder."
open ~/Desktop/"Java $sourcePKGVersion"