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5 things about Spooling in Cyber Security and How to Mitigate It

What is Spooling in Cyber Security?

"Spooling" is the act of storing data on a computer or network in reel-to-reel or other long-lasting media instead of a nonvolatile data storage medium such as a hard drive or a solid state drive. ( ) Spooling is an acronym for Simultaneous Peripheral Operation On-Line, and this allows the information to remain on a device even after that device is powered down or removed. Because spooling is nonvolatile, it does not require any power source to exist in order to use it. It is also more efficient.

Spooling attack technique used in cyber security to extract sensitive information from a system or remotely execute code. It is most often used to gain access to a system’s login credentials, but can also be used to steal data or deploy malware. Unlike traditional hacking techniques, which are intended to gain access to systems as quickly as possible, spooling is used to gain prolonged access to a system and is often used to steal sensitive information or launch additional attacks on a victim. Unlike traditional hacking techniques, which are intended to gain access to systems as quickly as possible, spooling is used to gain prolonged access to a system and is often used to steal sensitive information or launch additional attacks on a victim.

Unfortunately, the Spooling security risk is quite common especially due to the common use of Windows Printer Spooler service which is used by the majority of printers across the world. And in order to continue to build Digital Trust ( ) in an ever increasing digital world, efforts must be put forward to reduce spooling security risk and bolster threat management. ( )

Example of A Spooling Vulnerability

A Spooling attack exploits a vulnerability in the Spooling operating system, 

Spooling can be hijacked by threat actors to inject malevolent executions or code via a litany of methods. Most recently a vulnerability was discovered in Windows Print, a microsoft software used for printer devices.

A remote code execution vulnerability was discovered when the Windows Print Spooler service improperly performs privileged file operations. This, when properly and successfully exploited, allows for the threat actor to run arbitrary code with SYSTEM privileges. With very low attack complexity and high severities in the Confidentiality, Integrity and Availability metrics makes this a highly dangerous vulnerability. 

The only way to mitigate this attack would be to isolate affected systems and either dispose of them or try to replace the device the data was spooled upon.

Famous Spooling Attacks

In 2012, the Westboro Baptist Church, a hate group recognized by the ADL and FBI, known for ardent anti-gay beliefs and also protesting at the funerals of military personnel. In retaliation, the hacker group known as Anonymous conducted a cyber attack on the church’s technological infrastructure and website. ( )

By using a Window Printer Spooling attack they were able to inject an SQL command into the database of members allowing them access to the names, numbers, emails and addresses of all the members. They subsequently doxxed the members on 4chan which then spread to other social media platforms. This exploit also allowed them administrator access to several of the church members' terminals, to which the hackers pulled more data and also changed the desktop backgrounds to lewd imagery. In a separate attack they used a 0 day exploit to deface the church’s website during a livestream service.

This attack is one of the more famous spooling attacks, which really brought it into the mainstream media spotlight and brought more attention to the massive holes the Windows Print Spooling Service can put in an organization's security system.

How to Mitigate a Spooling Attack?

Because the Print Spooler is the default configuration for the majority of printer setups throughout the world, disabling the Print Spooler service on any computer or server connected to the internet is the simplest and most likely way to thwart a spooling assault. It's been discovered that the Print Spooler service isn't required for 90% of servers to run properly. (  

It's been discovered that some of the most vulnerable pieces of hardware in large networks, which are more likely to be attacked, don't require the Print Spooler service but have it enabled by default. The Print Spooler service should be disabled on domain controllers, Active Directory servers, member servers, and computers that don't need access to a printer. These simple steps will dramatically improve your threat management of this particular vulnerability.

It makes sense to re-equip those more sensitive computers and servers that do require print spooling with a non-Microsoft print spooling service. It's also a good idea to limit who has access to the Print Spooler service to only those who need it. This can help prevent unauthorized users from taking advantage of the service's flaws and bolster digital trust within your organization.

Patches and software upgrades should also be kept up to date to reduce the danger of an attack. However, there have been instances where Microsoft's upgrades or patches fail to fully resolve the issue or possibly worsen the situation. As a result, it's critical to back up your computers before applying fixes or installing upgrades. ( )

You can tell if you've been targeted by an attacker by looking at the PrintService log entries. In fact, one of the reasons why Print Spooler attacks are so successful is because of the requirement to monitor logs. Monitoring logs is a time-consuming task that frequently falls to the bottom of the To-Do list, allowing exploitations to go unnoticed.

Contact us to get a free evaluation today to discover more about how to protect your company from spooling and other cyber-attacks.

In Conclusion

Spooling attacks are incredibly low complexity attacks making it easy for threat actors to inject malicious code and successfully execute code remotely. This is a critical severity vulnerability and must be handled with the utmost urgency in patching and remediation of said vulnerability. I implore you to scour your organization to find any devices using Windows Print Spooler service and promptly uninstall the service. As stated above nearly 90% of printers will still function without the service. And always run quarterly penetration tests of your environment to ensure that you maintain solid security procedures and minimize vulnerabilities. As always, stay safe, secure, and prepared. ( )