CVE-2017-8759 in .NET Framework
Summary
by MITRE
Microsoft .NET Framework 2.0, 3.5, 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2 and 4.7 allow an attacker to execute code remotely via a malicious document or application, aka ".NET Framework Remote Code Execution Vulnerability."
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Analysis
by VulDB Data Team • 09/09/2024
The CVE-2017-8759 vulnerability represents a critical remote code execution flaw within Microsoft .NET Framework versions spanning from 2.0 through 4.7. This vulnerability arises from improper handling of specially crafted objects during the deserialization process within the framework's runtime environment. The flaw specifically affects the .NET Framework's ability to securely deserialize data structures, allowing maliciously crafted input to trigger arbitrary code execution when processed by applications built on these framework versions. The vulnerability is particularly dangerous because it can be exploited through various attack vectors including malicious documents, web applications, or any application that relies on .NET Framework deserialization mechanisms.
The technical implementation of this vulnerability stems from insufficient validation of data during the deserialization phase of .NET Framework applications. When applications process untrusted input through deserialization methods, the framework fails to properly validate the structure and content of the serialized data, creating opportunities for attackers to craft malicious payloads that execute arbitrary code with the privileges of the affected application. This flaw operates at the core of .NET Framework's object serialization and deserialization mechanisms, specifically affecting the BinaryFormatter and other related deserialization components. The vulnerability is classified under CWE-502 as Deserialization of Untrusted Data, which is a well-known weakness in software security that has been exploited in numerous high-profile attacks.
The operational impact of CVE-2017-8759 is severe and far-reaching across enterprise environments that utilize affected .NET Framework versions. Attackers can leverage this vulnerability to execute arbitrary code on targeted systems without requiring authentication, potentially leading to complete system compromise and lateral movement within networks. The vulnerability affects both server-side applications and client applications, making it particularly dangerous in environments where .NET Framework applications process untrusted data from external sources. Organizations running web applications, database applications, and enterprise software built on these framework versions face significant risk of exploitation, especially in environments where applications process data from untrusted sources such as user uploads, web services, or external APIs. The vulnerability aligns with ATT&CK technique T1203 - Exploitation for Client Execution, where adversaries leverage application vulnerabilities to execute malicious code on target systems.
Mitigation strategies for CVE-2017-8759 should prioritize immediate patching of affected systems with Microsoft security updates released in June 2017. Organizations should implement network segmentation and access controls to limit exposure of vulnerable applications to untrusted networks. Application-level mitigations include avoiding the use of dangerous deserialization methods such as BinaryFormatter and implementing proper input validation and sanitization. Security teams should monitor application logs for suspicious deserialization activities and implement intrusion detection systems to identify potential exploitation attempts. The vulnerability demonstrates the importance of secure coding practices and proper input validation as outlined in OWASP Top 10 and NIST Secure Coding guidelines. Organizations should also consider implementing application whitelisting policies and restricting the execution of untrusted code to minimize potential impact. Regular security assessments and vulnerability scanning should be conducted to identify and remediate similar vulnerabilities in other components of the application stack, as this type of flaw often indicates broader security gaps in software development practices.