SAP NetWeaver Enterprise Portal Administration is vulnerable if a privileged user uploads untrusted or malicious content that, upon deserialization, could result in a high impact on the confidentiality, integrity, and availability of the host system.
SAP NetWeaver Enterprise Portal Administration is susceptible to a critical vulnerability allowing a privileged user to upload malicious content. Successful exploitation leads to remote code execution (RCE), potentially compromising the confidentiality, integrity, and availability of the SAP system and underlying infrastructure. This vulnerability requires a privileged user to trigger, but the impact is severe, enabling complete system takeover.
Step 1: Privilege Escalation (Required): An attacker must first obtain or already possess administrative or privileged access to the SAP NetWeaver Enterprise Portal Administration interface. This could involve exploiting a separate vulnerability, credential theft, or social engineering.
Step 2: Payload Creation: The attacker crafts a malicious payload. This payload is typically a serialized object (e.g., Java object) designed to execute arbitrary code when deserialized by the SAP server. This payload will contain instructions for the server to execute malicious commands.
Step 3: Payload Upload: The attacker uploads the crafted payload through the SAP NetWeaver Enterprise Portal Administration interface. The specific upload mechanism will depend on the vulnerable component, but it will involve uploading a file.
Step 4: Deserialization Trigger: The uploaded payload is triggered by the server. This could be through a specific action within the administration interface, such as accessing a particular configuration setting or initiating a processing task that involves the uploaded file.
Step 5: Code Execution: The SAP server deserializes the malicious payload. The deserialization process executes the attacker-controlled code, leading to remote code execution (RCE) on the server. This allows the attacker to execute arbitrary commands with the privileges of the SAP user running the application.
The vulnerability stems from insecure deserialization of user-supplied data within the SAP NetWeaver Enterprise Portal Administration component. Specifically, the application fails to properly validate the contents of uploaded files before deserializing them. This allows an attacker to craft a malicious payload, typically in a serialized format like Java objects, that, when deserialized by the server, executes arbitrary code. The root cause is a lack of input validation and sanitization on the uploaded content, combined with the use of a deserialization function that is vulnerable to object injection. This allows an attacker to control the execution flow of the application.