A recent incident investigated by Huntress Labs has shed light on what attackers typically do once they’ve gained initial access to a compromised system. Rather than rushing to steal data or deploy ransomware, many attackers take their time to create backdoors, cover their tracks, and disable security tools.
The case in question involved an attacker who exploited a classic SQL injection vulnerability on a Microsoft SQL Server process. The flaw allowed the attacker to access the underlying Windows machine and gain a foothold in the system. From there, the attacker engaged in a series of deliberate actions to modify the environment to their advantage.
One of the first things the attacker did was to run a built-in Windows command that listed which services were running on the machine. This is a common recon step used by attackers to figure out what’s worth targeting or which processes they could disguise malicious activity as. The attacker then sent the results of this scan to a server they controlled, likely for later review or automated analysis.
The attacker next turned their attention to making the environment more conducive to further exploitation. They enabled Remote Desktop access, created a new user account and added it to the local Administrators group, giving them instant, high-level access that would survive a reboot or basic cleanup. They also disabled Windows Defender, Microsoft’s built-in antivirus, although they left other security monitoring tools untouched.
The attacker then installed malicious add-ons for the Internet Information Services (IIS) web server software running on the machine. These add-ons are part of a known malware family called BadIIS, which is typically used to hijack legitimate website traffic for search-engine fraud or redirect visitors to malicious sites.
In addition to these actions, the attacker also dropped a cryptocurrency mining program onto the machine. This common tactic allows attackers to squeeze extra value out of compromised systems by using their processing power to generate cryptocurrency on the victim’s electric bill. To keep this activity hidden, the attacker disguised the miner’s files and set it up to run as a Windows service.
The takeaway from this incident is that attackers often prioritize modifying the environment to their advantage over immediate data theft or ransom demands. Defenders should be aware of these tactics and take steps to prevent them, including regular security audits, network monitoring, and user education on best practices for avoiding SQL injection vulnerabilities.
Moreover, defenders should also be mindful of the types of malware that attackers are using and how they’re adapting their techniques. In this case, the use of BadIIS add-ons and cryptocurrency mining software highlights the importance of staying up-to-date with security patches and monitoring for suspicious activity. By being proactive and vigilant, defenders can reduce the risk of successful attacks and minimize the damage when they do occur.
Source: Bleeping Computer — 2026-07-30