CVE-2023-35298 in Windows
Summary
by MITRE • 07/11/2023
HTTP.sys Denial of Service Vulnerability
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 07/28/2023
This vulnerability resides within the HTTP protocol stack implementation in Microsoft Windows operating systems, specifically affecting the HTTP.sys kernel-mode driver that handles web requests. The flaw manifests as a remote code execution vulnerability that can be exploited through crafted HTTP requests sent to vulnerable systems, allowing attackers to trigger a denial of service condition that crashes the target system. The vulnerability stems from improper validation of HTTP request headers and body data within the Windows kernel, particularly when processing specially crafted requests containing malformed content length values or other header anomalies. This issue affects multiple Windows versions including windows 7, windows server 2008 r2, windows 8.1, windows server 2012, windows 10, and various server editions across the microsoft windows family. The technical implementation flaw falls under cwe-129 input validation and error handling weakness where insufficient bounds checking allows memory corruption during request processing. According to the attack technique catalog, this vulnerability maps to attack technique t14993 network denial of service which leverages protocol implementation flaws to exhaust system resources or cause crashes. The operational impact extends beyond simple service disruption as compromised systems may require complete reboot cycles and could potentially provide attackers with opportunities for privilege escalation if exploited in conjunction with other vulnerabilities.
The exploitation mechanism relies on sending specially crafted HTTP requests that trigger buffer overflows or memory corruption within the http.sys driver when processing malformed headers or content length values. Attackers can leverage this vulnerability without authentication requirements, making it particularly dangerous as it allows remote attackers to cause system crashes simply by accessing vulnerable web services. The vulnerability affects both internet information services iis and other applications relying on the http.sys kernel driver for web request handling. When exploited successfully, the target system experiences a blue screen of death or complete system hang requiring manual intervention to restore normal operation. Systems running windows server 2016, windows server 2019, and windows 10 versions are also affected if they have http.sys components enabled, though some configurations may be less vulnerable depending on specific service deployments.
Mitigation strategies include applying microsoft security patches immediately upon release, disabling unnecessary web services that rely on http.sys, and implementing network level restrictions to prevent unauthorized access to vulnerable systems. organizations should also deploy intrusion detection systems capable of identifying malformed http requests that may indicate exploitation attempts. the recommended approach involves configuring windows firewall rules to block potentially malicious traffic patterns and deploying application layer firewalls that can inspect http content for known attack signatures. additionally, administrators should consider disabling http.sys functionality if not required for business operations and ensure regular security updates are applied through microsoft update services or other automated patch management solutions. compliance with nist cybersecurity framework and iso 27001 standards requires implementing these controls to maintain system integrity and prevent unauthorized access. organizations should also conduct regular vulnerability assessments to identify any remaining systems that may be affected and establish incident response procedures for rapid remediation when exploitation attempts are detected. the vulnerability represents a critical risk to enterprise environments where web services are exposed to untrusted networks, requiring immediate attention through coordinated security measures across all affected systems.