Recently researches were able to find a loop hole in SSL certificate implementation which could could make any secure website (relying on md5 hashing of CA certificates) vulnerable to nearly undetectable phishing attack.

To brief the attack:

1. CA (certicate authorities) issue their certificates hashed , md5 and SHA1 being the most popular.

2. However few CAs like Verisign (RapidSSL), Microsoft and Mozilla use md5 implementation which is insecure in nature. This md5 hole (md5 collision) was disclosed by few chinese cryptogaphers few years back.

3. Researches discovered they could create a fake certificate and issue them on behalf of the CA.

4. They did a PoC by hosting a rouge website and requestd RapidSSL for a certificate. They then lifted Rapid SSL’s signing authority in order to sign and issue other certificates.
5. The researchers were able to impersonate a legitimate Website, complete with the padlock icon that accompanies actual secured sites.

Moore says the most worrisome risk would be countries using the hack to monitor SSL-encrypted links. “The specific case I see the most worrying is state-level. A country like China, the UAE, or possibly Australia [if the new law passes there] could use this to transparently monitor all SSL-encrypted communications going into and out of their countries,” he says. “For all we know, this is already happening.”

The other issue is that SSL certificates signed by MD5 will still be out there even after the CA’s switch to SHA-1, so there’s no way to know if sites with those certs are truly legitimate. “Many of them have multiyear expirations,” notes Moore. “Any fake keys signed by that same root key would still be valid and they [CAs] can’t revoke the key without causing a lot of pain to their customers. I’m interested in seeing how this gets addressed. There aren’t any good solutions to it.”

There’s also no way to know for sure if such an attack has already occurred on the Net, the researchers say, but it would take some significant firepower to pull it off. “The computing and technical competency requirements make this tough for a casual attacker,” Moore says.

And this isn’t just an SSL problem, Graham points out. “This is an entire PKI infrastructure problem,” he says.

This attack combined with Dan’s DNS spoofing attack can literally launch a undetectable phishing attack. CAs need to switch from MD5 to SHA1 or later. Customers can review their certificates and ensure they are signed using SHA-1 or higher. Even that wouldn’t help in some scenarios. To see that, double-click the lock icon and “View Certificate”. Check the “Certificate Signature Algorithm”.

So be alert while logging into net banking sites. I wuould keep my bank’s IP handy. This way, I guess can be much safer to log into my account.

Similar Posts you might be interested in:

• Phishing attack takes a twist – Beware backtalkers
• Some issue at Yahoo??? Your accounts can be deleted…
• Hacking Yahoo, Gmail or any Bank accounts.

2 Responses to “Secure websites are not so secure”

1. russ says:

   January 4, 2009 at 4:46 pm

   even scarier – you could sign an activex control / java applet with a forged certificate. I can see the malware ‘industry’ jumping on this pretty quick!
2. w0lf says:

   January 6, 2009 at 9:49 am

   Yes. you are right. Hope that all CA switch to SHA1 or later before its late