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CVE-2021-23758 is an unsafe deserialization vulnerability in Ajax.NET Professional (AjaxPro/AjaxNetProfessional). The framework insufficiently validates user-supplied JSON containing type information, permitting deserialization of arbitrary .NET classes. This can enable unauthenticated remote code execution in the context of the vulnerable application. Versions prior to 21.11.29.1 are affected.
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2 valid exploits after Mallory filtered fakes, detection scripts, and README-only repos.
This repository contains a single Metasploit module (modules/exploits/windows/http/ajaxpro_deserialization_rce.rb) that exploits a remote code execution vulnerability (CVE-2021-23758) in Ajax.NET Professional (AjaxPro) for Windows. The exploit targets an insecure deserialization flaw in the AjaxPro JsonDeserializer, allowing attackers to execute arbitrary commands on the server by sending specially crafted JSON data to a vulnerable HTTP endpoint. The module supports both direct command execution and staged payloads (such as Meterpreter reverse shells), leveraging Metasploit's payload system. The exploit is weaponized, allowing for customizable payloads and automated exploitation. The main endpoints targeted are the AjaxPro handler paths (e.g., /ajaxpro/, /core.ashx, and the vulnerable namespace/method .ashx endpoint). The module is configurable for different namespaces, methods, and parameters, making it adaptable to various AjaxPro deployments. The repository is structured as a typical Metasploit exploit module, written in Ruby, and is intended for use within the Metasploit Framework.
This repository is a proof-of-concept (POC) exploit for CVE-2021-23758, a critical deserialization vulnerability in Ajax.NET Professional (AjaxPro) for ASP.NET. The exploit demonstrates how an attacker can achieve remote code execution (RCE) by sending a specially crafted POST request to a vulnerable AjaxPro handler (e.g., /ajaxpro/CVE_2021_23758_POC.demo,CVE_2021_23758.ashx). The payload leverages .NET's JavaScriptSerializer to deserialize a malicious ObjectDataProvider object, which in turn launches an arbitrary process (calc.exe in the POC). The repository contains a full ASP.NET WebForms project, including the vulnerable handler, demo pages, and all necessary configuration files. The main exploit vector is network-based, requiring access to the vulnerable HTTP endpoint. The exploit is operational and demonstrates real code execution, but is not weaponized for mass exploitation. The repository structure is typical for a Visual Studio ASP.NET project, with C# source files, ASPX pages, configuration files, and supporting scripts and styles. The README provides clear instructions and a sample payload, as well as references to ysoserial.net for payload generation.
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24 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
A CVSS 8.1 deserialization-of-untrusted-data vulnerability affecting Ajax.NET Professional and listed in CISA's KEV catalog.
An Ajax.NET deserialization vulnerability added to CISA's Known Exploited Vulnerabilities catalog.
An Ajax.NET Professional (AjaxPro) insecure-deserialization vulnerability that can enable remote code execution via arbitrary .NET classes.
A deserialization-of-untrusted-data vulnerability in Ajax.NET Professional. It may be dangerous where attacker-controlled serialized data reaches application components without adequate validation.
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Cross-references every affected SKU, including bundled OEM variants.
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