Revealing the Hidden Threat: The Imminent Peril to MSSQL Servers

by | Jul 3, 2023

The realm of cyberattacks is an ever-present threat, and currently, there is a formidable target under siege: Microsoft SQL Server (MSSQL). This widely-used database management system, seamlessly integrated with Windows servers, has become a prime hunting ground for hackers due to its popularity and the array of tools developed for it. Shockingly, there are over 450,000 exposed instances of MSSQL on the internet, with a staggering 133,000 in China alone. The threat to MSSQL servers is growing at an alarming rate.

Fortunately, diligent researchers at Trustwave have been closely monitoring this unsettling trend. Through their tireless efforts, they have uncovered a range of techniques employed by attackers to compromise MSSQL servers. These tactics range from the download and execution of malicious files to the exploitation of the system’s extensibility features, which grant hackers control over vulnerable servers. One vulnerability that attackers eagerly exploit is the Object Linking and Embedding (OLE) automation procedure, enabling them to execute arbitrary code within the database engine. By abusing the potent capabilities of OLE Automation and CLR assembly, attackers can gain escalated privileges, expanding their dominion over the server.

Hackers often rely on brute-force credential guessing attacks to access MSSQL servers, with the default “sa” account as their primary target. While changing default administrative accounts to strong and unique credentials is undeniably crucial, it does not provide foolproof protection against attacks. Disabling unnecessary features within the database and reducing its attack surface is an additional essential step.

However, attackers are relentless in their pursuit. Trustwave researchers discovered that even with efforts to secure MSSQL servers, their honeypots experienced over 3 million login attempts during peak attack periods. Regional preferences were evident, with China hosting the highest number of exposed MSSQL servers, while the United Kingdom emerged as the most targeted country.

Exploiting the integration between MSSQL and other Windows components, such as Component Object Model (COM) and .NET Framework CLR Integration, is another favorite tactic of attackers. By leveraging these integrations, they can execute malicious code, deploy Trojan programs, and even install backdoor CLR assemblies, granting them persistent access to compromised servers.

Given the escalating threats against MSSQL servers, organizations must implement robust security measures. Alongside enforcing strong password policies, disabling unnecessary features can significantly reduce the attack surface. However, it is crucial to note that attackers with administrative privileges can easily re-enable these features, underscoring the need for continuous monitoring and proactive security practices.

As the cyber landscape continues to evolve, organizations must remain vigilant and take proactive steps to secure their MSSQL servers. Regular vulnerability assessments, timely patching, and ongoing security awareness training for administrators are crucial in mitigating risks. By adopting a multi-layered security approach, organizations can fortify their MSSQL servers against the ever-growing threat landscape.

In conclusion, the surge in attacks targeting MSSQL servers serves as a stark reminder of the need for heightened security measures. With attackers exploiting weak credentials, abusing powerful features, and leveraging integrations with other Windows components, organizations must prioritize securing their databases. By comprehending the evolving tactics employed by hackers and implementing robust security practices, organizations can safeguard their valuable data and prevent potentially catastrophic breaches. The battle to protect MSSQL servers rages on, and organizations must strive to stay one step ahead in the ongoing fight against cybercrime.