Exploit.ByteVerify is a means of penetration into computers using the vulnerability in Microsoft Virtual Machine, build 5.0.3809 inclusive.
The detailed description of this flaw in Microsoft’s software appeared in our news dated 09.04.2003.
The disclosure of the vulnerability and the patch release gave birth to a series of Trojan Horses, utilizing this exploit.
The computer becomes Trojan affected at simple viewing of a web-site with malicious Java-script embedded into it. Another way for them to tunnel into systems is to be executed by a user himself from HTML- attachment, received vi e-mail. An ill-intentioned Java-applet downloads from the internet and installs a Trojan program exploiting the ByteVerify vulnerability. Besides, the Trojan of this family can perform the following actions in the victimized machine:
it secures its automatic launch at every system startup
the Troj may considerably degrade the performance of Internet Explorer
when alphabetic symbols are typed into specified fields they will be displayed on the screen with some delay
if non-existing URL mistyped by a user or the address without www is entered into a search bar the default «Server is not found» page will not appear, instead, the browser will be redirected to a web-site determined in the Trojan’s code
links to dubious web-sites are added into Favourites folder
search bar is replaced
user stylesheet is replaced with Trojan’s own stylesheet file
when searching with Google, Yahoo, MSN and Altavista the Troj provoke multiple popup windows to show up
it can disguise its presence in a system as a driver update
If the operating system (OS) can be loaded (either normally or in safe mode), download Dr.Web Security Space and run a full scan of your computer and removable media you use. More about Dr.Web Security Space.
If you cannot boot the OS, change the BIOS settings to boot your system from a CD or USB drive. Download the image of the emergency system repair disk Dr.Web® LiveDisk , mount it on a USB drive or burn it to a CD/DVD. After booting up with this media, run a full scan and cure all the detected threats.
If the mobile device is operating normally, download and install Dr.Web for Android. Run a full system scan and follow recommendations to neutralize the detected threats.
If the mobile device has been locked by Android.Locker ransomware (the message on the screen tells you that you have broken some law or demands a set ransom amount; or you will see some other announcement that prevents you from using the handheld normally), do the following:
Load your smartphone or tablet in the safe mode (depending on the operating system version and specifications of the particular mobile device involved, this procedure can be performed in various ways; seek clarification from the user guide that was shipped with the device, or contact its manufacturer);
Once you have activated safe mode, install the Dr.Web for Android onto the infected handheld and run a full scan of the system; follow the steps recommended for neutralizing the threats that have been detected;