CVE-2022-21167 in Masuit.Tools
Summary
by MITRE • 05/01/2022
All versions of package masuit.tools.core are vulnerable to Arbitrary Code Execution via the ReceiveVarData function in the SocketClient.cs component. The socket client in the package can pass in the payload via the user-controllable input after it has been established, because this socket client transmission does not have the appropriate restrictions or type bindings for the BinaryFormatter.
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Analysis
by VulDB Data Team • 05/04/2022
The vulnerability identified as CVE-2022-21167 affects the masuit.tools.core package, specifically targeting versions that implement a socket client component with insecure deserialization practices. This flaw exists within the SocketClient.cs file where the ReceiveVarData function processes incoming data without proper validation or type restrictions, creating a critical security risk that allows attackers to execute arbitrary code on affected systems. The vulnerability stems from the package's reliance on BinaryFormatter for data transmission, which lacks proper input sanitization and type binding mechanisms that would normally prevent malicious payloads from being executed during deserialization processes.
The technical implementation of this vulnerability leverages the dangerous nature of BinaryFormatter in .NET applications, which can deserialize arbitrary objects from untrusted input streams. When the socket client receives data through the ReceiveVarData function, it processes the payload without verifying its contents or ensuring proper type constraints, allowing attackers to craft malicious serialized objects that will be executed when the data is deserialized. This represents a classic deserialization vulnerability that aligns with CWE-502, which specifically addresses the deserialization of untrusted data, and follows patterns commonly seen in exploit frameworks targeting .NET environments.
The operational impact of this vulnerability is severe as it provides remote attackers with complete system compromise capabilities through a single network-based attack vector. An attacker can establish a connection to the vulnerable service and inject malicious serialized data that gets executed within the context of the running application, potentially leading to full system control, data exfiltration, or lateral movement within network environments. The vulnerability is particularly dangerous because it can be exploited without requiring authentication, making it a prime target for automated exploitation tools that scan for vulnerable services across the internet.
Mitigation strategies for CVE-2022-21167 must address the core deserialization flaw by implementing proper input validation, type restrictions, and secure serialization practices. Organizations should immediately update to patched versions of the masuit.tools.core package where available, or implement alternative serialization methods that do not rely on BinaryFormatter. Security measures should include network segmentation to limit exposure of vulnerable services, implementing proper input validation at all network boundaries, and monitoring for unusual network traffic patterns that might indicate exploitation attempts. Additionally, following ATT&CK framework techniques for defensive operations, organizations should implement process monitoring and anomaly detection to identify potential exploitation of this vulnerability through the use of binary payload delivery mechanisms that bypass traditional security controls.