October is a cyber security awareness month so lets start it with the most hilarious web security awareness video I’ve ever seen.
The other day I received an email from a webmaster whose site was blacklisted by Google. In Webmaster Tools, he found the following example of a malicious code detected on his site (domain changed):
<img src="http://example .net/images/logos/rssicon.png" />
So why did Google think this image tag was malicious? Can images be malicious? After all they are not scripts, iframes or embedded executable objects that that hackers use to attack web surfers.
I actively work with Google’s Safe Browsing diagnostic pages. They are a great source of information if you know how to interpret them. I usually read several dozen such diagnostic pages a day. Unfortunately, the readability of the diagnostic pages is quite poor.
To make my life easier, I created a simple script that highlighted important information so that I could see everything I needed at a glance. I had been using that script for more than a year before the recent Firefox 4 upgrade broke it (the technology I used is deprecated now). This was a serious loss for me. Every time I opened Safe Browsing diagnostic pages (several dozen times a day) I missed my script. Even though I knew the page layout very well, it took significantly more efforts to extract the same amount of information. The difference was almost the same as you might feel when you have to use a touchpad instead of a normal mouse.
Recently, I helped one company to remediate security problems with their four websites. It was quite an usual iframe injection attack. FTP logs clearly showed how attackers used FTP to infect legitimate files on server. So the question was, how could FTP credentials be stolen?
Of course, I pointed them to my blog post where I described how malware stole passwords and all the login details saved in 10 most popular FTP clients (e.g. Filezilla, CuteFTP, Total Commander, etc.). Indeed, recent malware scan revealed two suspicious items on their computer. One of them was identified as “Spyware.Passwords“. The only problem was the site owner said they didn’t use those FTP clients and kept all passwords in KeePass. Moreover, they manages 50 websites and only four of them got infected.
The answer became quite clear when they found an old copy of SmartFTP on their computer. There had been 5 FTP account (including passwords) saved there. Four of them were the four hacked sites! So what about the fifth? No doubt all five site credentials had been stolen, but the fifth site wasn’t hacked because its password had been changed after the last use of SmartFTP — so the stolen password was not valid by the moment of the hacker attack. This also explains why the rest 45 sites were not hacked — their passwords weren’t stolen.
Not only should you avoid saving passwords in your current FTP client, but also make sure they are not saved in old programs that may still reside on your computer.
This year, most successful malware attacks against legitimate websites used stolen FTP credentials. I always suggest that you don’t store passwords in your FTP programs where they are easily accessible by any program running on your computer (including malware). For example, in FileZilla, FTP passwords are stored as plain text in configuration files. And FileZilla is not the only FTP client malware authors target in their hunt for website credentials.
In the recent post about Quicksilver malware network, you can read that the trojan behind the infamous iframe injection attack “looks for all kinds of configuration files of ftp programs in their default install paths“. I contacted the researcher and asked if he had a full list of the FTP clients this malware looks for.
And here’s the list »»
2009 is the year of malware attacks that use stolen FTP credentials to infect legitimate web sites. Hundreds of thousands websites have been hacked this way and suffered from hidden iframe injections, Gumblar, redirections to bogus anti-virus sites, etc.
The success of those attacks is based on the fact that a significant percentage of web surfer are webmasters and site owners themselves. Once a computer of a site owner is infected, malware can steal his/her FTP credentials and use them to make the site distribute malware to unsuspecting visitors, who, in turn, may also be site owners. As a result, we see rapid growth in number of compromised websites.
There are quite a few hypotheses about how cibercriminals steal the credentials: traffic sniffing, using keyloggers, etc. But the most viable is that trojans simply extract everything they need from configuration files of popular FTP programs. Let me show how easy it can be done.
WordPress has just released a security update.
WordPress 2.8.2 fixes an XSS vulnerability. Comment author URLs were not fully sanitized when displayed in the admin. This could be exploited to redirect you away from the admin to another site
Unfortunately, the official blog didn’t mention that this upgrade is actually critical and why you should update ASAP. Let me explain this.
This must be not a new attack (I’ve found an almost year old article that mentions gcounter iframes) but I started to notice it this past weekend. First, on the Google’s Webmaster Forums, then in the Unmask Parasites logs. So I guess it’s a new wave of the attack.
When I first encountered a site infected by gcounter, I checked it with Unmask Parasites. Nothing suspicious was found except for the fact that the domain name was blacklisted by Google. I checked the diagnostic page and found this clue:
Malicious software is hosted on 1 domain(s), including gcounter.cn/.