CAPEC-30: Hijacking a Privileged Thread of Execution
CAPEC版本: 3.9
更新日期: 2023-01-24
攻击模式描述
An adversary hijacks a privileged thread of execution by injecting malicious code into a running process. By using a privleged thread to do their bidding, adversaries can evade process-based detection that would stop an attack that creates a new process. This can lead to an adversary gaining access to the process's memory and can also enable elevated privileges. The most common way to perform this attack is by suspending an existing thread and manipulating its memory.
执行流程
步骤 1 Explore
[Determine target thread] The adversary determines the underlying system thread that is subject to user-control
步骤 2 Experiment
[Gain handle to thread] The adversary then gains a handle to a process thread.
- Use the "OpenThread" API call in Windows on a known thread.
- Cause an exception in a java privileged block public function and catch it, or catch a normal signal. The thread is then hanging and the adversary can attempt to gain a handle to it.
步骤 3 Experiment
[Alter process memory] Once the adversary has a handle to the target thread, they will suspend the thread and alter the memory using native OS calls.
- On Windows, use "SuspendThread" followed by "VirtualAllocEx", "WriteProcessMemory", and "SetThreadContext".
步骤 4 Exploit
[Resume thread execution] Once the process memory has been altered to execute malicious code, the thread is then resumed.
- On Windows, use "ResumeThread".
前提条件
- The application in question employs a threaded model of execution with the threads operating at, or having the ability to switch to, a higher privilege level than normal users
- In order to feasibly execute this class of attacks, the adversary must have the ability to hijack a privileged thread. This ability includes, but is not limited to, modifying environment variables that affect the process the thread belongs to, or calling native OS calls that can suspend and alter process memory. This does not preclude network-based attacks, but makes them conceptually more difficult to identify and execute.
所需技能
所需资源
后果影响
影响范围: Confidentiality Access Control Authorization
技术影响: Gain Privileges
影响范围: Confidentiality Integrity Availability
技术影响: Execute Unauthorized Commands
说明: Run Arbitrary Code
缓解措施
Application Architects must be careful to design callback, signal, and similar asynchronous constructs such that they shed excess privilege prior to handing control to user-written (thus untrusted) code.
Application Architects must be careful to design privileged code blocks such that upon return (successful, failed, or unpredicted) that privilege is shed prior to leaving the block/scope.
示例实例
Adversary targets an application written using Java's AWT, with the 1.2.2 era event model. In this circumstance, any AWTEvent originating in the underlying OS (such as a mouse click) would return a privileged thread (e.g., a system call). The adversary could choose to not return the AWT-generated thread upon consuming the event, but instead leveraging its privilege to conduct privileged operations.
分类映射
| 分类名称 | 条目ID | 条目名称 |
|---|---|---|
| ATTACK | 1055.003 | Process Injection: Thread Execution Hijacking |