Discovered: December 25, 2004
Updated: February 13, 2007 12:31:12 PM
Systems Affected: UNIX
Perl.Santy.B is a worm written in Perl script that attempts to spread to Web servers running versions of the phpBB 2.x bulletin board software prior to 2.0.11, which are vulnerable to the PHPBB Viewtopic.PHP PHP Script Injection Vulnerability (BID 10701 ). It uses AOL or Yahoo search to find potential new infection targets.
Antivirus Protection Dates
- Initial Rapid Release version December 26, 2004
- Latest Rapid Release version August 08, 2016 revision 023
- Initial Daily Certified version December 26, 2004
- Latest Daily Certified version August 09, 2016 revision 001
- Initial Weekly Certified release date December 29, 2004
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.
When Perl.Santy.B is executed, it does the following:
- Tries to obtain scripts from other compromised forums.
Possible filenames of the script include:
NOTE: At the time of creating this writeup, the aforementioned files have been removed from the server. Symantec Security Response has received reports that these scripts attempt to perform various actions, such as opening backdoors and connecting to IRC channels, but has been unable to verify this due to the absence of these files.
- Searches for "viewtopic.php" using the AOL or Yahoo search engine to generate a list of possible infection targets.
- Attempts to exploit the PHPBB Viewtopic.PHP PHP Script Injection Vulnerability (BID 10701) to obtain access to the remote Web server.
- Attempts to delete the following files from hosts it infects:
Symantec Security Response encourages all users and administrators to adhere to the following basic security "best practices":
- Use a firewall to block all incoming connections from the Internet to services that should not be publicly available. By default, you should deny all incoming connections and only allow services you explicitly want to offer to the outside world.
- Enforce a password policy. Complex passwords make it difficult to crack password files on compromised computers. This helps to prevent or limit damage when a computer is compromised.
- Ensure that programs and users of the computer use the lowest level of privileges necessary to complete a task. When prompted for a root or UAC password, ensure that the program asking for administration-level access is a legitimate application.
- Disable AutoPlay to prevent the automatic launching of executable files on network and removable drives, and disconnect the drives when not required. If write access is not required, enable read-only mode if the option is available.
- Turn off file sharing if not needed. If file sharing is required, use ACLs and password protection to limit access. Disable anonymous access to shared folders. Grant access only to user accounts with strong passwords to folders that must be shared.
- Turn off and remove unnecessary services. By default, many operating systems install auxiliary services that are not critical. These services are avenues of attack. If they are removed, threats have less avenues of attack.
- If a threat exploits one or more network services, disable, or block access to, those services until a patch is applied.
- Always keep your patch levels up-to-date, especially on computers that host public services and are accessible through the firewall, such as HTTP, FTP, mail, and DNS services.
- Configure your email server to block or remove email that contains file attachments that are commonly used to spread threats, such as .vbs, .bat, .exe, .pif and .scr files.
- Isolate compromised computers quickly to prevent threats from spreading further. Perform a forensic analysis and restore the computers using trusted media.
- Train employees not to open attachments unless they are expecting them. Also, do not execute software that is downloaded from the Internet unless it has been scanned for viruses. Simply visiting a compromised Web site can cause infection if certain browser vulnerabilities are not patched.
- If Bluetooth is not required for mobile devices, it should be turned off. If you require its use, ensure that the device's visibility is set to "Hidden" so that it cannot be scanned by other Bluetooth devices. If device pairing must be used, ensure that all devices are set to "Unauthorized", requiring authorization for each connection request. Do not accept applications that are unsigned or sent from unknown sources.
- For further information on the terms used in this document, please refer to the Security Response glossary.
The following instructions pertain to all current and recent Symantec antivirus products, including the Symantec AntiVirus and Norton AntiVirus product lines.
- Update the virus definitions.
- Run a full system scan and delete all the files detected as Perl.Santy.B.
- If necessary, update phpBB to 2.0.11 or above.
For specific details on each of these steps, read the following instructions.
1. To update the virus definitions
Symantec Security Response fully tests all the virus definitions for quality assurance before they are posted to our servers. There are two ways to obtain the most recent virus definitions:
- Running LiveUpdate, which is the easiest way to obtain virus definitions: These virus definitions are posted to the LiveUpdate servers once each week (usually on Wednesdays), unless there is a major virus outbreak. To determine whether definitions for this threat are available by LiveUpdate, refer to the Virus Definitions (LiveUpdate).
- Downloading the definitions using the Intelligent Updater: The Intelligent Updater virus definitions are posted daily. You should download the definitions from the Symantec Security Response Web site and manually install them. To determine whether definitions for this threat are available by the Intelligent Updater, refer to the Virus Definitions (Intelligent Updater).
The Intelligent Updater virus definitions are available: Read "How to update virus definition files using the Intelligent Updater" for detailed instructions.
2. To scan for and delete the infected files
- Start your Symantec antivirus program and make sure that it is configured to scan all the files.
- For Norton AntiVirus consumer products: Read the document, "How to configure Norton AntiVirus to scan all files."
- For Symantec AntiVirus Enterprise products: Read the document, "How to verify that a Symantec Corporate antivirus product is set to scan all files."
- Run a full system scan.
- If any files are detected as infected with Perl.Santy.B, click Delete.