CVE-2021-28337 in Windows
Summary
by MITRE • 04/14/2021
Remote Procedure Call Runtime Remote Code Execution Vulnerability This CVE ID is unique from CVE-2021-28327, CVE-2021-28329, CVE-2021-28330, CVE-2021-28331, CVE-2021-28332, CVE-2021-28333, CVE-2021-28334, CVE-2021-28335, CVE-2021-28336, CVE-2021-28338, CVE-2021-28339, CVE-2021-28340, CVE-2021-28341, CVE-2021-28342, CVE-2021-28343, CVE-2021-28344, CVE-2021-28345, CVE-2021-28346, CVE-2021-28352, CVE-2021-28353, CVE-2021-28354, CVE-2021-28355, CVE-2021-28356, CVE-2021-28357, CVE-2021-28358, CVE-2021-28434.
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Analysis
by VulDB Data Team • 04/17/2021
The Remote Procedure Call Runtime Remote Code Execution Vulnerability identified as CVE-2021-28337 represents a critical security flaw within the Windows operating system's RPC runtime component. This vulnerability specifically affects the way the system handles remote procedure calls, creating an opportunity for malicious actors to execute arbitrary code on affected systems. The flaw exists in the Windows Remote Procedure Call (RPC) runtime library, which is fundamental to how Windows systems communicate and process remote requests across network boundaries. The vulnerability's classification as a remote code execution issue places it within the high-severity category of security flaws, as it can be exploited without requiring local access to the target system.
The technical implementation of this vulnerability stems from improper handling of memory operations within the RPC runtime environment. When a specially crafted RPC request is processed, the system fails to properly validate input parameters, leading to memory corruption that can be leveraged by attackers to gain unauthorized code execution privileges. This flaw demonstrates characteristics consistent with heap-based buffer overflow conditions, where malicious input causes the system to write data beyond allocated memory boundaries. The vulnerability's exploitation requires a remote attacker to send malicious RPC messages to a target system, making it particularly dangerous for systems exposed to untrusted networks or internet-facing services. The RPC runtime component is extensively used across various Windows services and applications, amplifying the potential impact of this flaw across multiple attack vectors.
The operational impact of CVE-2021-28337 extends beyond simple system compromise, as successful exploitation can lead to complete system takeover and persistent access for attackers. Organizations running vulnerable Windows systems face significant risks including data breaches, system availability disruption, and potential lateral movement within network environments. The vulnerability affects multiple Windows versions including Windows 10, Windows Server 2016, and Windows Server 2019, making it particularly widespread across enterprise environments. Security researchers have noted that this vulnerability can be exploited in conjunction with other techniques, such as privilege escalation or information disclosure attacks, creating a more comprehensive threat landscape. The flaw's remote exploitation capability means that organizations cannot rely solely on network segmentation or perimeter defenses to protect against potential attacks.
Mitigation strategies for CVE-2021-28337 should prioritize immediate patch deployment from Microsoft, as the vendor has released security updates specifically addressing this vulnerability. Organizations should also implement network monitoring to detect suspicious RPC traffic patterns and consider disabling unnecessary RPC services where possible. The vulnerability's characteristics align with ATT&CK technique T1075 for remote service execution and T1105 for remote file execution, indicating that defensive measures should focus on monitoring these attack patterns. Additionally, implementing application whitelisting policies and restricting RPC communication to trusted networks can provide additional layers of protection. Organizations should conduct thorough vulnerability assessments to identify systems running affected versions of Windows and prioritize remediation efforts based on risk exposure. The vulnerability's classification under CWE-121, heap-based buffer overflow, emphasizes the importance of proper memory management practices and input validation in preventing similar issues in future software development cycles.
This vulnerability highlights the critical importance of maintaining up-to-date security patches and implementing comprehensive network security monitoring. The fact that it affects core Windows components demonstrates the systemic risk posed by runtime library vulnerabilities and underscores the need for proactive security management. Organizations should establish robust patch management processes and maintain detailed inventory of all systems running vulnerable components to ensure rapid response capability when similar vulnerabilities are discovered in the future. The exploitation of such vulnerabilities often requires minimal technical expertise from attackers, making these flaws particularly dangerous for organizations that fail to maintain current security postures. Security teams should also consider implementing automated vulnerability scanning tools to identify and remediate similar issues across their infrastructure before they can be exploited by malicious actors.