Welcome to the Virus Encyclopedia of Panda Security.
It carries out damaging actions on the affected computer.
It does not spread automatically using its own means.
|First detected on:||Feb. 2, 2004|
|Detection updated on:||Feb. 2, 2004|
|Yes, using TruPrevent Technologies
Stepan is a virus that spreads to other computers by copying its code to other files or programs.
Stepan uses the following propagation or distribution methods:
- Exploiting vulnerabilities with the intervention of the user: exploiting vulnerabilities in file formats or applications. To exploit them successfully it needs the intervention of the user: opening files, viewing malicious web pages, reading emails, etc.
- File infection: it infects different types of files, which are then distributed through any of the usual means: floppy disks, email messages with attachments, Internet download, files transferred via FTP, IRC channels, P2P file sharing networks, etc.
Stepan uses the following infection strategies:
- Resident: once it has been run, the virus goes memory resident and stops functions belonging to the operating system. Therefore, every time the operating system or an application tries to access any of these functions, the virus will activate and infect new files.
- Polymorphic: it encrypts itself in a different way with each infection it carries out. In order to do this, it uses different keys and operations. As a result, the virus has different characteristics in each new infection, which makes it difficult for antivirus pro-grams to detect this virus.
- Encrypted: it encrypts its code in order to make it difficult to detect. In order to carry out its infection, the virus decrypts itself and, once infection has been carried out, it encrypts itself again.
- Cavity: it infects files without modifying their size or corrupting the data they contain, as it takes advantage of the cavities in these files to insert its code.