As you might know, I maintain and regularly update a list of Gumblar zombie URLs. The main reason why I do it is to help webmasters of compromised sites find relevant information about the source of their problems and the steps required to clean up and secure their sites. I see this pattern quite often, when webmasters find a suspicious script in their web pages and use it in Google searches to find more information about it. On the other hand, this list can also help reveal the security breach of sites that hackers use to host Gumblar zombie scripts.
This week the list has reached the level of 1,000+ URLs. Although it’s just a small part of all Gumblar zombie scripts, this list makes a good base for a quick analysis of Gumblar zombie URLs.
Continue »»
About a month ago I wrote about a hacker attack that used hijacked subdomains of legitimate websites to serve malware (fake anti-virus software) off of them. Most likely cyber criminals used a phishing attack to steal credentials of GoDaddy’s domain management control panel and created rogue DNS records for some subdomains to make them point to hacker-controlled servers.
In that article I wondered if that was a new trend (usage of virtually free hijacked subdomains) or just temporary approach that wouldn’t be used anywhere else. Well, this week I came across a different malware attack that also uses hijacked subdomains of legitimate websites.
Continue »»
Selected short messages and links you might have missed if you don’t follow me on Twitter.
Selected short messages and links you might have missed if you don’t follow me on Twitter.
Injecting hidden malicious iframes into compromised legitimate websites is one of the most popular types of malware attacks. Invisible iframes allow to silently load exploits from “bad” sites while unsuspecting web surfers browsing visible content of infected websites.
Iframes are rectangular elements of webpages where you can load other web pages either from the same site or from some third party site (in other words: webpage inside a webpage). There are many legitimate uses of iframes. The most common is ad blocks (e.g. Google displays AdSense in iframes)
It is said that iframes are rectangular elements and they occupy some space on web pages. So how do hackers make them invisible?
Continue »»
Do you remember Gumblar? The massive hacker attack that managed to infect more than a hundred thousand legitimate web sites in a very short time this May? The infection was relatively easy to detect but very hard to completely get rid of. It infected various types of files and created backdoor scripts in inconspicuous places of websites so that hackers could easily restore the malicious content.
The gumblar .cn site (and its immediate successor martuz .cn) had been promptly shut down. As a result,the malicious script injected into hacked websites became harmless for site visitors. However, many webmasters failed to properly clean up their sites after the Gumblar infection, leaving the backdoor scripts intact. It was predicted that hackers would find the way to utilize this army of potentially controllable websites. Now, five months later, we see a new surge of a massive attack that resembles Gumblar in many aspects.
Continue »»
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 »»
Selected short messages and links you might have missed if you don’t follow me on Twitter.
Continue »»