August 2008

SCO? Anybody home?

I have been trying to contact the guys at SCO to report a serious vulnerability in their operating system as part of our SSD program, with very little success:

All the emails I send there return with this funny bounce message:

Sorry. Although I’m listed as a best-preference MX or A for that host, it isn’t in my control/locals file, so I don’t treat it as local. (#5.4.6)

A few other emails I sent to people I used to know there, bounced with the same message.

If anyone from SCO reads this post, or you know someone that can help me reach those guys, I would be grateful if you can contact me.

    SecuriTeam Secure Disclosure

    SecuriTeam Secure Disclosure (SSD) helps researchers turn their vulnerability discovery skills into a highly paid career. Contact SSD to get the most for your hard work.

Fedora confirms: Our servers were breached

It is more than week ago when The Fedora Project informed about “important issue” affecting to its infrastructure systems. No additional details were given.
As expected, the claims and rumors started to spread if there was a serious server breach.

The Fedora Project issued a recommendation that users will not download any packages or update their Fedora installations. There was a note to change the Fedora Project passwords (it was not reported widely for some reason) too.

Today, Mr. Paul W. Frields, Fedora Project Leader has posted an announcement about the facts:

One of the compromised Fedora servers was a system used for signing Fedora packages. However, based on our efforts, we have high confidence that the intruder was not able to capture the passphrase used to secure the Fedora package signing key. Based on our review to date, the passphrase was not used during the time of the intrusion on the system and the passphrase is not stored on any of the Fedora servers.

While there is no definitive evidence that the Fedora key has been compromised, because Fedora packages are distributed via multiple third-party mirrors and repositories, we have decided to convert to new Fedora signing keys. This may require affirmative steps from every Fedora system owner or administrator. We will widely and clearly communicate any such steps to help users when available.

The Fedora Project servers are hosted at Red Hat Inc., the employee of Mr. Frields.

This is an interesting detail from hosting history section: – Linux Apache/2.2.3 Red Hat – 19-Aug-2008 – Linux Apache/2.2.0 Fedora   – 16-Aug-2008 – Linux Apache/2.2.3 Red Hat – 19-Aug-2008

    SecuriTeam Secure Disclosure

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Nokia & Sun: Yes, Nokia S40 J2ME vulnerabilities exist

I have never understood news articles using terms like ‘claims’ and ‘rumors’ when reporting about several vulnerabilities reported in Nokia Series 40 (S40) phones.

Adam Gowdiak from Poland is a well known researcher, man behind Windows RPC issue MS03-026 etc.

Sun has confirmed that older versions of Java 2 Platform Micro Edition (J2ME) are affected (this was on 15h Aug already) and Nokia confirmed these issues today (let’s say, at last).

It is not known if Sun Microsystems or Nokia Corp. paid €20 000 to Gowdiak, last week or possible later.

Some references:

Security Explorations: J2ME security vulnerabilities 2008
MIDP’s and MIDlets put tens of millions Nokia S40 phones in danger

Update 22nd Aug: From

“Gowdiak would not disclose if he was paid, but said that only reputable, vetted companies that pay would get the full research, which amounted to 180 pages and 14,000 lines of proof-of-concept code.

Nokia has a complete copy of Gowdiak’s research, said Mark Durrant of Nokia’s corporate communications.”

    SecuriTeam Secure Disclosure

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Getting Paid For Others’ Work

As I was turning to signal my waitress for the bill, I noticed that aside the couple at the corner, everybody else was hooked to their laptops. Time has changed and now people sit in cafes for wireless internet, a play list on shuffle and some good cappuccino. Even though we are all mixing business with pleasure, we are just like the next guy: we eat, we Google, we Facebook.

But I’m not here to talk about aroma, I’m here to explain how you can get money for somebody else’s work.

Tap the airwaves and play a role of a man-in-the-middle. When you’re right in the center of things, imagine doing these:

  • Grep and replace adsense code blocks with your own pub-id. You will get paid, and not the owner of the website.
  • Shove 1×1 px iframes to Amazon with your affiliation tag. These will store a cookie on the victim’s browser with your tag. Even if she buys a book a week later, you will still get your hard-earned pay.
  • Replace facebook ads with affiliation blocks.
  • Proxy DNS lookups, and if dns resolve fails, show ads instead.

So how is it done? Quite simple, wlan is merely ethernet network over airwaves. It deals with the same concepts, IPs, MACs and ARPs. Whenever a program wishes to connect to a remote box (outside your netmask,) it will route the requests via the gateway. This gateway is the wireless router you laptop is connected to. Computers inside the local area network communicate in ethernet protocol, so when my laptop sends an IP packet to the gateway, it wraps it up with an ethernet header. ARP is a protocol used to associate IP addresses with MAC addresses.

The brunette next to the magazine stand is using her laptop. Since we are both connected to the same gateway, we are on the same subnet. Using a nifty tool called arping, I can send an arp announce (also named “Gratuitous ARP“) to her computer, forcing it to associate the gateway IP address with my laptop mac address. So whenever she browses the internet, my computer will receive all the packets.

I have no idea what’s her IP address, and it doesn’t really matter. I can just broadcast an ARP announcement and update all arp caches in this subnet. Consider the following command line:
C:\>arping -i “\Device\NPF_{031C071A-8ED1-4AD9-8FD6-A930D4FA15F9}” -v -S -s 00-1b-77-53-f7-2f -B

This will broadcast (-B) an arp announcement of the address (-S) (gw) with the mac address (-s) of my laptop. Use Wireshark to find out the interface name (-i) of your wireless adapter. If you are targeting a single computer, replace -B with the ip address of the victim.

Note that broadcasting to the entire subnet will also damage your own arp cache table. To re-associate with the real mac address, clean entry with ‘arp -d’.

Unlike other approaches for man-in-the-middle attack, this one keeps you hidden. Unless you make it obvious, people won’t suspect. After all, it hijacks an existing router, does not require reconnecting and I am pretty sure nobody keeps record of their arp table.

Remember, just don’t be a jerk.

    SecuriTeam Secure Disclosure

    SecuriTeam Secure Disclosure (SSD) helps researchers turn their vulnerability discovery skills into a highly paid career. Contact SSD to get the most for your hard work.

Vanity Search Attacks

“How did you two meet? Did you mark her, or was it the other way around?”

– Robert Redford to Brad Pit, Spy Game

Con man 101: The best way to gain someone’s confidence is to make them think they contacted you. Scammers just love having potential victims contacting them.

Now, it seems they figured an interesting way to draw potential victims to their web site, in a way that is much easier than sending billions of spam email messages.
The idea is simple: take the person’s name (real people’s names are available for harvesting in places like linkedin, facebook, and other social networks) and put it in a web page. Doesn’t really matter where, as long as google indexes it.

Wait a while, and have that person google himself. Many people (myself included) have a ‘google alert’ on their name which sends them updated list of links to new pages where their name is mentioned.

Everyone likes to see where they are mentioned, so they will click on the link. And voila! They arrive to the spammer’s page. In some cases I’ve seen, the name was already gone from the page (but was still in the google cache). But all this doesn’t matter: as soon as the person reached the page, the web spammer’s job is done – he got his message in front of you, and maybe you’ll even dig deeper into his web site trying to figure out what the connection is to you.

There are many advantages to this method. First, you are not restricted by the message: the web page can openly have the words Viagra, Credit card debt and mortgage assistance without the fear of triggering anti-spam software. Also, people will pay more attention to the page since they think it has to do with them.

I don’t get the spammers’ marketing statistics, but I’m sure that the infamous spam text “it came to our attention that you’re in dire need of financial help” which sounds very much like a sincere, personal message, is a huge success. But this message has to get through the spam filters and include a real email address and a correct first/last name. The spam web page doesn’t need to bypass spam filters, and already has the correct name. In addition, you gain interesting information about the visitor: browser version, IP location and of course, the name he was searching for (that would be in the ‘referrer’ that is sent automatically by the browser to the web site). Oh, and of course – it’s cheap. You only need to put together a nice looking web page, and wait for google to do the rest. No buying of email lists and no cost of sending spam (which is nowadays the cost of hiring a zombie botnet for a couple of days).

For those aspiring scammers who are reading this, you should understand that it’s not a foolproof method. Obviously, it requires people to do a vanity search to reach you in the first place (though it also works on people who google their dates, their parents or their teachers). It also requires time – days, weeks or months (which may be difficult if your web site is on a zombie computer that might disappear by the time google indexes and the user comes to the site). But due to the fact the costs are very small, and there are no effective countermeasures at the moment, I think we will see more and more such attacks in the near future.

    SecuriTeam Secure Disclosure

    SecuriTeam Secure Disclosure (SSD) helps researchers turn their vulnerability discovery skills into a highly paid career. Contact SSD to get the most for your hard work.

The Security Question Vulnerability

How easy is it to break into your Gmail account? How about Yahoo! Or Windows Live?
If you provided a truthful answer to the security question during signup, it is probably quite easy to hijack your account, with just a little bit of a research.

Take a look at the Yahoo! Security Questions:

Yahoo Security Questions

Are these security questions?

Anyone that knows my address can easily figure out the name of my first school or my high school mascot. All of my neighbors, family and friends know both my dog’s name and my dad’s middle name, and everybody in the world knows I just LOVE the Lakers. As for my wife and me, the people who attended our wedding had the chance to hear about it in the ceremony – in case you couldn’t make it, we met on a roof of a bus, in Ladakh, India in 1994…

The fact that the answer to each of the security questions above is relatively easy to find out, makes them a security vulnerability in my Yahoo! account.
By letting me make a security key based on the name of my first school, Yahoo! actually puts me at risk, allowing anyone that knows where I live to hijack my account. It’s like saying “We have the greatest lock to protect your house. Now, why don’t we hide the key under the mat”.

Windows Live is pretty much the same as Yahoo!:

windows live security questions
Gmail is a little bit more sophisticated with one major difference:
gmail security questions

Gmail is the only one of these three that allows you to choose your own question.
By letting you do that, Gmail asks “which question only you can answer?” I think that most people might still come up with “Who is my favorite singer”, “What is my date of birth” or “My dog’s name”.
However, that isn’t a security vulnerability encouraged by Google. If they give you the tools and you fail to use them, it’s not their fault.

So, what can we do about it?
If you can write your own question, How to unblock Facebook that would be the best. If not, choose the question about the name of your first school and put your first phone number as the answer. That’s what I did! :)
Got better ideas? Share them with us!

    SecuriTeam Secure Disclosure

    SecuriTeam Secure Disclosure (SSD) helps researchers turn their vulnerability discovery skills into a highly paid career. Contact SSD to get the most for your hard work.

That device on my work computer – was it there yesterday?

Bank robbers using remote control device to control the mouse cursor of bank employee have been jailed now, report the headlines.

We can’t expect that an ordinary worker will know if USB sticks, peripherals with Bluetooth enabled, innocent looking hardware keyloggers etc. connected to their desktop computers and even to laptops are malicious – and not installed by a local IT support.

This Swedish worker recognized an odd device connected to his workstation, but a target organization is not so lucky every time. ”Employee quickly pulled the plug, interrupting a transfer” ($7.9 million), but there was an extra cable which ended up under his desk.

It’s worth of mentioning that this remote control device had been installed to bank workstation during a previous break-in, during which nothing had been stolen from the building.

Therefore, the ways how we can protect against these threats are not so typical:

* Check the USB and PS/2 connectors of your workstations and servers several times a year
* Always check these connectors when a computer returns from being repaired
* Remember that visitors have a possibility to connect these devices often

    SecuriTeam Secure Disclosure

    SecuriTeam Secure Disclosure (SSD) helps researchers turn their vulnerability discovery skills into a highly paid career. Contact SSD to get the most for your hard work.