Software Engineering Institute

According to Microsoft, the Print Spooler service is

...an executable file that is installed as a service. The spooler is loaded when the operating system starts, and it continues to run until the operating system is shut down. The Print Spooler service manages the printing process, which includes such tasks as retrieving the location of the correct printer driver, loading that driver, spooling high-level function calls into a print job, and scheduling print jobs.

The Print Spooler service (sploolsv.exe) does not properly handle incoming messages, potentially allowing a buffer overflow to occur. If a remote attacker can convince a user to connect to a malicious print server, that attacker may be able to trigger the buffer overflow.

For more information, please refer to MS05-043.

An unauthenticated remote attacker may be able to execute arbitrary code on a vulnerable system. In addition, this vulnerability can be exploited locally by an attacker that has a valid user account on a vulnerable system.

Apply an update

Microsoft has addressed this issue in Microsoft Security Bulletin MS05-043.

Disable the Print Spooler service

Microsoft recommends disabling the Print Spooler service to mitigate this vulnerability. MS05-043 lists the following steps to disable the service:

1. Click Start, and then click Control Panel. Alternatively, point to Settings, and then click Control Panel.
2. Double-click Administrative Tools.
3. Double-click Services.
4. Double-click Print Spooler.
5. In the Startup type list, click Disabled.
6. Click Stop, and then click OK.

In addition, issuing the following command from a command prompt will disable the Print Spooler service:

sc stop Spooler & sc config Spooler start= disabled

Note that disabling or removing the Print Spooler service on a system will prevent that system from being able to print either locally or remotely.