IFRAME Injection Attacks Via FTP

Back in May and continuing into June, we saw a sharpThis could result in a serious decrease in traffic to
increase in the number of compromised websites dueyour site, and a loss of confidence by your visitors in
to the Gumblar infection. This virus/malware wouldthe trustworthiness of your company. In addition to
infect a PC, and then pass any FTP usernames andGoogle Safe Browsing, other anti-virus programs may
passwords it could find stored in any FTP program onalso block your site, increasing the impact of this
the computer back to the Botnet. The hackers wouldcompromise.
then use this FTP information to upload malicious"What can be done?" Here are a few things you can
code into webpages to continue to infect more PCs.do to clean this up, clean up your PC, and keep
These attacks lessened in July, but August hasthings secure moving forward:
brought a new wave of these infections. The latest
variants are similar to the original Gumblar virus: They1. The first thing to do is clean your infected web
collect FTP usernames and passwords from infectedfiles. Your web host should be able to provide you
PCs, and pass these login credentials back to thewith a log of uploaded files by the hackers. They
creators of the malware. The hackers then havemay even be able to restore infected files from
automated "bots" that log into a website via FTP,backup. If not, download the infected files, remove
download every file that starts with main, index, orthe IFRAME code, and re-upload.
default, insert an IFRAME (a hidden frame that can2. Next, try to determine which PC or PCs are
be loaded on a website) either right after the "" htmlinfected with malware (any PC that had your FTP u
tag or at the end of the file (especially with php files)p stored could be the source, even a developer's PC
and then re-upload this altered webpage to theor outsourced designer/programmer). Make sure your
hosting account.anti-virus software is fully up to date, and run a full
Unsuspecting visitors to these webpages may havescan. Our clients have had great success using
their PCs also become compromised, and the virusMalwareBytes Anti-malware to compliment their
continues to spread. Many people often think theseregular anti-virus software.
attacks are due to a compromised script on the3. Once the infected PCs are clean, change your FTP
website, or that the hosting company's server waspassword as soon as possible.
hacked/compromised allowing hackers to replace files.4. Continue to monitor your web pages and FTP logs
Although these two scenarios are possible, it's quiteto make sure the incident does not recur. If you find
easy to determine if an FTP compromise was theout that a developer or outsourced programmer was
culprit:the point of origin, consider giving them limited FTP
- FTP Log Files Ask your host to check the FTP logsaccess to a specific folder to upload their changes so
for the latest logins to your account. This will be anthey do not have account access to your live web
easy way to determine if the compromise was viapages.
FTP. If it was, the log will likely show many logins5. Consider using a secure FTP connection such as
from many different IP numbers and locations.FTPS or SFTP to work with your files in your hosting
"What's the Harm?" Besides the obvious of havingaccount.
your account compromised and vulnerable toHackers are realizing that it's much easier to attack
defacing, and the spreading of a virus via yourthe weakest link to infiltrate websites and servers -
website, it is very possible that services such aspersonal computers that often are not running the
Google Safe Browsing will list your site as potentiallylatest patches or up to date security software, and
harmful, and many people using the Firefox or Googlewhose users may not pay enough attention when
Chrome web browser will be greeted with a warningclicking links and allowing malicious code to run.
when they try to go to your site.