Protect Your Windows Computer from HTTP.sys Denial of Service Attacks

CVSScvssV3_1: 7.5

Microsoft’s HTTP.sys component is responsible for handling HTTP traffic in Windows. According to a new vulnerability disclosed by Microsoft, it is possible for attackers to cause a denial of service (DoS) condition in HTTP.sys, preventing legitimate users from accessing websites or web services.

The vulnerability, tracked as CVE-2023-32084, has a CVSS score of 7.5 out of 10 indicating its potential impact. It can be exploited by sending specially crafted HTTP requests to targets running unpatched versions of Windows. This may cause HTTP.sys to stop responding, blocking all HTTP traffic until the system is restarted.

While the technical details are still under wraps, in general these kinds of HTTP request flooding attacks work by overwhelming server resources with more traffic than it can handle. For HTTP.sys, it appears abnormal or malformed requests are able to crash the component running on the target system.

The good news is Microsoft has already provided an update to fix this issue. Windows users are advised to install all available security patches as soon as possible to protect themselves. It’s also recommended to use a firewall and only expose services to the internet if they really need to be accessible publicly. Taking basic precautions can go a long way in preventing exploitation.

Staying on top of software and system updates is one of the best ways to plug security holes before attackers can take advantage of them. So be sure to automate updates where possible and always install them promptly for important components like HTTP.sys that interact directly with the internet.