Process hollowing functions First, the attacker must choose a legitimate system process to hollow. Mar 4, 2025 · In this blog post, we explain the T1055. Recently… How Do You Perform Process Hollowing? From a big-picture perspective, process hollowing requires the following steps in order to execute code. Windows process hollowing works by creating a suspended process and writing the shellcode over the entry point of the process’s main thread. Oct 14, 2021 · 這篇文章將會介紹 Process Hollowing 的原理並輔以程式碼片段加以解說。 根據 Mitre att&ck 的分類，Process Hollowing 是 Process Injection 的一門子類別，又可稱為 cross-process injection。這次的程式展示將以 Windows 作業系統為目標，Windows 的執行檔統稱 portable executables (PE)，因此此項技法又名為 Portable Executable Oct 6, 2024 · The attacker then suspends the main thread of the process and unmaps its memory space using the ZeroMemory or MapViewOfSection functions. The process hollowing technique is used for unpacking. The attacker-controlled malicious process spawns a new process, which we will refer to as the victim process. Jan 16, 2024 · Process hollowing refers to a method where the memory of a legitimate system process is replaced with malicious code. k. This is accomplished by manipulating the process memory, specifically the part that contains the executable code. exe process is launched as a child of the process we select. Feb 3, 2025 · A longstanding malware technique known as Process Hollowing or RunPE has encountered compatibility issues on this latest Windows update, leading to broader discussions about the evolving landscape of cybersecurity. Sep 7, 2024 · Process hollowing on Windows. The image base address is obtained from the process information using the PROCESS_BASIC_INFORMATION struct. In many cases, the malware will perform obfuscation/encoding and additional methods to disguise the process, making the identification of Process Hollowing more complex. Process-Hollowing has no bugs, it has no vulnerabilities, it has a Strong Copyleft License and it has low support. Check if the PE image have a valid signature. W elcome back to my Malware Development series. a RunPE) – as in older samples of Trickbot. winitor. There are several techniques, which are commonly used: DLL injection, process replacement (a. This is typically a process that is commonly running on the system and is less likely to raise suspicion, such as svchost. When the legitimate process is hollowed, the malware code is injected into the new process and executed. HollowGhost performs process hollowing injection into svchost. To implement process hollowing on Windows, one can use the CreateProcess function. Aug 27, 2024 · The hollowing process follows these steps: Replacement: Attackers start by creating a legitimate process, usually by calling the CreateProcess function in Windows. Process hollowing has been used by malware to masquerade their code as legitimate processes. Oct 9, 2017 · A technique used by malware author to evade defenses and detection analysis of malicious processes execution Process hollowing is a technique used by malware in which a legitimate process is loaded on the system solely to act as a container for hostile code. Process hollowing occurs when a malware unmaps (hollows out) the legitimate code from memory of the target process, and overwrites the memory space of the Process hollowing is yet another tool in the kit of those who seek to hide the presence of a process. CreateProcessA is a Windows API function that creates a new process and its primary thread. Apr 28, 2019 · Process Hollowing occurs when a malware creates a benign process in a suspended state and then unmaps and replaces the process memory with malicious code. exe on Windows. Feb 23, 2022 · Injecting code into explorer. Scripts permettant de contourner la protection antivirale de Windows Defender via la technique de Process Hollowing avec une injection de shellcode préalablement obfusqué avec un fonction XOR. Injecting Malicious Code : Inject your payload into the empty space Feb 3, 2025 · Process Hollowing is a sophisticated code injection technique often used by malware to evade detection. This means that I can now perform process hollowing and I will be using notepad. We observed that in this case the process hollowing is done using direct system calls, in a way that is very similar to the Flokibot malware. Feb 3, 2025 · Process Hollowing is a sophisticated code injection technique often used by malware to evade detection. Process hollowing is a method of executing arbitrary code in the address space of a separate live process. exe) with arbitrary code while masquerading PEB, under a legitimate parent process (explorer. Process Doppelgänging, on the other hand, writes the Oct 18, 2024 · Technical Details of Master Process Hollowing. Process Hollowing is a code injection technique commonly employed by malware to evade detection. exe), empty/hollow out the executable’s image in its memory, and then write the content of the malicious code into that virtual memory space of the victim’s process. This process hollowing implementation is written in C++, the loader is a x64 executable with can inject into x86 and x64 processes. Oct 1, 2024 · Generally, Process Hollowing is mostly used to run a PE under other process. For researchers and developers relying on process hollowing, these changes necessitate either adopting new methodologies or implementing targeted patches to maintain compatibility. g. So as you can see there is two new structures that I used, STARTUPINFOA and PROCESS_INFORMATION, which are two crucial structures that provide information about the startup configuration and state of the new process and its primary thread. . team about process hollowing if you want to have more details about the basics. Nov 15, 2024 · Detecting process hollowing can be challenging, as it involves legitimate Windows API functions. If we find a modules that the EXE depends on (if it's written on the EXE's IAT) but we don't find it in the process memory, that indicate that the process is hollowed and have been replaced with another EXE. a process hollowing), hook injection and APC injection. It has dwCreationFlags parameter that can include a CREATE_SUSPENDED flag resulting in the process newly created to be in a “suspended” state, waiting for the creator process to resume it. PHDetection looks for modules that the original EXE is depends on, and check if they are loaded in the process memory. Indeed, we will be using a calc. Windows Process Injection - Process Hollowing July 06, 2021 @ochsenmeier Marc Ochsenmeier www. The legitimate process is resumed, but now it’s executing the attacker’s code. Process hollowing C# shellcode runner that is FUD against Microsoft Defender as of October 7, 2023. Hollowise is a Windows-based tool that implements process hollowing and PPID (Parent Process ID) spoofing techniques. This shellcode runner is currently FUD by Microsoft Defender at scan-time, runtime, and during on-demand scanning with an active shell. This method involves creating a new process in a suspended state and then replacing its code with malicious content. How it works? At launch, the legitimate process is created in a suspended state and the process’s memory is replaced with the code of a After successfully creating the process, the program queries information about the process using ZwQueryInformationProcess from ntdll. This helps the malware evade detection as it appears to be running from a legitimate process, making it harder to distinguish from normal system Oct 8, 2024 · The key difference between Process Hollowing and Process Injection lies in their execution flow. First, the attacker creates a new process in a suspended state using the CreateProcess function with the CREATE_SUSPENDED flag. See full list on hackingarticles. exe , using the Windows API function CreateProcess . The loader make severals checks before trying to inject the new PE image. first; Hello brothers, today I am going to explain anti reversing technique which also is a technique of process injection before digging deep into the details of this method, first we need to explain what process hollowing is, after that, I will explain with code snippets and APIs Jul 29, 2024 · First, I check for the correct number of arguments: the host process executable and the malicious executable. Process Hollowing (a. This lab is my attempt to better understand and implement a well known code injection technique called process hollowing, where a victim process is created in a suspended state, its image is carved out from memory, a malicious binary gets written instead and the program state is resumed to execute the injected code. in Dec 7, 2024 · Process hollowing, or Hollow Process Injection, is a stealthy technique used by malware to execute malicious code within the address space of a legitimate process. Apr 23, 2024 · In the generic implementation, a call will be made to certain Windows API functions, which we will review now. In Process Hollowing, the malware hijacks a legitimate process and replaces its entire code space . It then resumes the suspended process, which in turn executes the shellcode. In contrast, Process Injection involves injecting malicious code into an already running process without necessarily replacing the original code This process hollowing implementation is written in C++, the loader is a x64 executable with can inject into x86 and x64 processes. cpp content in dll. Process hollowing is a sophisticated code injection technique used by cyber attackers to run malicious code under the guise of a legitimate process. A bit of calculation is then needed to Figure 1 shows the libraries used, along with a declaration of ZwUnmapViewofSection(), which will be used to hollow the process. Sep 19, 2023 · How Process Hollowing Works. Finally, the attacker injects malicious code into the hollowed process, allowing it to execute undetected. The malware creates a new process using the CreateProcess function. Also Jun 14, 2020 · Thanks to malwarebytes for the images :) Process Hollowing first initiates the target process, then unmaps and injects the malicious code. Since I know (after my analysis) that this function performs process hollowing, I renamed it to Sub_ProcessHollow. dll -shared dll. Sep 27, 2024 · Technical Aspects of Process Hollowing. PowerShell implementation of shellcode based Process Hollowing that only relies on dynamically resolved Win32 API functions - DynWin32-ShellcodeProcessHollowing. A victim process can be created with native Windows API calls such as CreateProcess, which includes a flag to suspend the processes primary thread. We can now execute code inside a target process at will and have the process running flawlessly. May 30, 2024 · At its core, process hollowing involves the insertion and execution of malicious code within the address space of a legitimate process, paving the way for surreptitious infiltration and subversion of system functions. exe by having it point to the newly injected code in its view, after which it resumes the suspended calc. Tổng quan Process Hollowing. exe process, and the process handle can be found in the PROCESS_INFORMATION struct which was passed as a parameter during the CreateProcessA API call. exe, give your own xor secret Copy obfuscated-shellcode. dll. The code then reads the PE header of the newly created process to locate the entry point address. Persistent code injection. Oct 13, 2024 · Introduction to Process Hollowing. exe). However, there are several methods that can be employed to detect this technique: One approach is to monitor the system for suspicious API calls , such as the creation of a new process in a suspended state, followed by the unmapping of its original Nov 19, 2024 · How Process Hollowing Works. Jan 30, 2025 · Process hollowing is a multi-stage process that requires a deep understanding of the Windows operating system and its underlying mechanics. , DLL injection), malware can perform a technique known as process hollowing. Most of them use same Windows API functions: OpenProcess, VirtualAllocEx, WriteProcessMemory, for detailed information about those functions, use MSDN. Process hollowing is commonly performed by creating a process in a suspended state then unmapping/hollowing its memory, which can then be replaced with malicious code. It was also used in one of the demos involving my library, libPEconv. cpp C:\msys64 Aug 13, 2018 · Classic Process Doppelgänging: Process Hollowing: Osiris Loader: Creating a new process. Điều này được gọi là Process Hollowing. Process hollowing is a sophisticated malware technique that involves hijacking a legitimate process to execute malicious code, making it challenging for security systems to detect. Jun 23, 2021 · Overview of Process Hollowing aka (Process Replacement/RunPE) Instead of injecting code into a host program (e. Once resumed, the process appears legitimate while executing harmful actions in disguise. 1. Process Hollowing is a sophisticated code injection technique often used by malware to evade detection. calc. Then, in Figure 2, the main() function begins by initializing two structures, STARTUPINFOA(), and PROCESS_INFORMATION(), which are used to help populate the CreateProcessA() API, which will be used to start our Dec 31, 2024 · Process Hollowing Prevention Tips. exe process/thread, which should run the injected code. Oct 13, 2024 · Hollowing Out the Process: Unmap the original legitimate code from memory, leaving the process as an empty container. Then they replace the code of this process with a malicious payload. Detection and Prevention Techniques. I suggest to read the article from ired. Feb 3, 2025 · Description . 012 Process Hollowing technique of the MITRE ATT&CK® framework and explore how adversaries employ process hollowing with real-world attack examples in detail. The function takes several Aug 9, 2022 · Process Hollowing is a sub-injection technique mainly used by attackers to evade the potential process-based defenses. Dec 28, 2016 · Process Hollowing Analysis For Malware Detection . Process hollowing is commonly used in advanced persistent threats (APTs), ransomware, and fileless malware, making it a critical security concern. The Osiris loader starts by creating the process into which it is going to inject. In our case, the target process is the suspended notepad. exe process running (our destination process). ps1 Apr 28, 2019 · Performing process hollowing (function sub_4010EA) After dropping and decrypting its embedded resource in memory, the malware calls the function sub_4010EA. exe or rundll32. Defense Evasion, Privilege Escalation: Process Injection: Process Hollowing (T1055. It is used in variety of PE loaders, PoCs, and offensive tooling. Process hollowing is a form of code injection, a broad category of cyber-attack techniques that involve inserting malicious code into an existing software process. exe is not trivial to evade detection as these processes generally do not generate any network activity. Here’s how: 1. To detect and prevent process hollowing attacks, security Jan 28, 2023 · In the process hollowing code injection technique, an attacker creates a new process in a suspended state, its image is then unmapped (hollowed) from the memory, a malicious binary gets written Nov 22, 2017 · A brief recap: what is Process Hollowing? Process hollowing is a technique used by malware in which a legitimate process is loaded on the system solely to act as a container for hostile code: the legitimate process is launched in a suspended state and its memory area is replaced with the code of a second program that will be executed instead of Dec 25, 2024 · Process hollowing is a variant of code injection attacks, where an attacker creates a new process in a suspended state and then replaces its memory with malicious code. How it works? At launch, the legitimate process is created in a suspended state and the process’s memory is replaced with the code of a Điều này được gọi là Process Hollowing. cpp : C:\msys64\mingw64\bin\x86_64-w64-mingw32-c++. Essentially, the Windows binary is loaded in a suspended state and the memory belonging to the process is overwritten with malicious code and then unsuspended. exe or notepad. exe (line 42) will be written to the hollowed notepad. exe (line 28) as the destination process and regshot. From a technical standpoint, master process hollowing involves several key steps. The svchost. 012) Adversaries may inject malicious code into suspended and hollowed processes to evade process-based defenses. A malware that uses process hollowing starts a target ** process with CREATE_SUSPENDED flag enabled. This new variant makes use of process hollowing (a. Aug 19, 2020 · The idea of this technique is that the malware launcher will create a new process from the victim’s executable(e. The original process is hollowed out and continues running surreptitiously under its original context, disguising the execution of embedded malicious code. This flag allows the process to be created without executing its primary thread. Dec 12, 2024 · Process hollowing involves creating a new instance of a legitimate process in a suspended state, unmapping the original code from the process’s memory space, and replacing it with malicious code. Execute obfu. Process hollowing is a technique to run executable, binary code, while disguised as a different process. cpp and launcher. The malware then uses the OpenProcess function to obtain a handle to the newly created process, and the VirtualAllocEx function to allocate memory within the process. Create a new instance of a legitimate process such as svchost. It allows for stealth execution of debuggers and code and network analizers by replacing the memory of a suspended process (e. The legitimate image is then unmapped and replaced with the image that is to May 14, 2024 · WriteProcessMemory is a Windows API function that requires a handle to the target process with the necessary access rights (PROCESS_VM_WRITE and PROCESS_VM_OPERATION). It involves creating a benign process in a suspended state, removing its executable code, injecting malicious code, altering the entry point, and then resuming the process. Jan 27, 2025 · Process Hollowing (a. exe. Process-Hollowing is a C++ library typically used in Artificial Intelligence, Dataset applications. Check if the target process and the PE image May 12, 2016 · Would it be possible for a "process hollowing scanner" to enumerate all the executable pages in a process' memory, enumerate all the executable sections of the process' associated image file, and see if there were any pages in the memory that didn't have any corresponding pages in the image file, for example by fuzzy hashing the image file “ברוב” – כי ה – Malware Sample שנראה בקרוב מממש Process Injection,ובדיוק הוא, לא משתמש ב – Windows API Functions האלו😉. Jul 4, 2023 · Resume the process: Finally, the process is resumed using the ResumeThread or NtResumeThread function, which allows the malicious code to start executing within the context of the legitimate process. Then using the handler it got from created the process, it hollows out the legitimate executable image from the target process’s Feb 17, 2023 · Process Hollowing 3 minute read On this page. com الجزء الثالث Process Hollowing تطبيق تكنيك ال (10:18) الجزء الرابع Process Hollowing تطبيق تكنيك ال (8:03) May 20, 2022 · Basic process injection using ptrace and mmap. May 6, 2023 · When calling the NtUnmapViewOfSection function, two arguments are required: the process handle and the base address of the target process. Process hollowing typically begins with the creation of a new process using the Windows CreateProcess function in a suspended state. The process is created by a function from Kernel32: CreateProcessInternalW: The new process (wermgr. אז בואו נתחיל לרברס🤩 Process Hollowing. The last improvement looks much better, but it's relatively useless to inject code into another process if it's just going to perform some actions and exit; we could have executed the injected code directly to the same effect. Process hollowing is a method of running arbitrary code in the address space of a separate live process. exe system process is a shared service process that allows several services to share this process to reduce resource consumption, which usually generates network activity. cpp file and update shellcode char array variable in process hollowing functions Compile dll. exe process: Below is a powershell one-liner that constantly checks if there's a notepad. Process hollowing is a process of running a new process in the address space of a preexisting process. Even though, today we will see how to do it directly with shellcode as it is way much easier. In contrast, Process Injection involves injecting malicious code into an already running process without necessarily replacing the original code Process hollowing. Oct 8, 2024 · The key difference between Process Hollowing and Process Injection lies in their execution flow. The legitimate image is then unmapped and replaced with the image that is to be hidden. Feb 3, 2025 · While alternatives like Transacted Hollowing and Process Overwriting provide viable paths forward, they require additional complexity and trade-offs in stealth. Although its main use is to evade detection by anti-viruses, process hollowing also has a legitimate use. The idea is rather straight forward: a bootstrap application creates a seemingly innocent process in a suspended state. Apr 19, 2023 · I'm currently trying to implement some sort of a process hollowing (RunPE) technique, using C. - ProcessusT/Bypass-AV-ProcessHollowing An implementation of the Process Hollowing technique. exe) is created in a suspended state from the original file. ; Allocate memory in the new process with VirtualAllocEx() ensuring the memory region Process hollowing. Process hollowing involves creating a new process in a suspended state, then unmapping its memory and replacing it with malicious code. Process Hollowing works as follows: The malware creates a benign process in a suspended state (API function used: CreateProcessA). This helps the malware evade detection as it appears to be running from a legitimate process, making it harder to distinguish from normal system AL2025_05 New Process Hollowing Attack Vectors Uncovered in Windows 11 (24H2) (03rd February 2025) Description Process Hollowing is a code injection technique commonly employed by malware to evade detection. Điểm qua quy trình tạo một Process thông qua API CreateProcess ta có : Tạo Memory Space cho Process mới; Phân bổ stack cùng với "Thread Environment Block" và "Process Environment Block" Loads DLL hoặc EXE vào bộ nhớ Sep 19, 2023 · How Process Hollowing Works. The process is then resumed, allowing the malicious code to execute under the guise of a legitimate process. a. Linux process hollowing functions a little differently. Basically what I've done so far, is find the PEB and get the process's (in suspended mode) image base Aug 14, 2018 · Trickbot process hollowing using direct system calls. exe or explorer. Check if the target process and the PE image Process hollowing is commonly performed by creating a process in a suspended state then unmapping/hollowing its memory, which can then be replaced with malicious code. The attacker achieves this by using the Windows API functions CreateProcess , SuspendThread , VirtualAllocEx , WriteProcessMemory , and ResumeThread . How can you prevent process hollowing attacks? Process hollowing is a stealthy malware technique, but several proactive security measures can help detect and prevent these attacks. It involves creating a legitimate process in a suspended state, hollowing out its memory, and replacing it with malicious code. By understanding the technical details of process hollowing and implementing effective detection and mitigation strategies, security professionals can better protect systems Feb 9, 2025 · What is Process Hollowing? If we take a look at MITRE ATT&CK which is a global knowledge base of adversary tactics and techniques we see the following description for process hollowing Jul 8, 2024 · Process Hollowing. explorer. So far, it Jan 1, 2022 · Process hollowing technique works by hollowing out a legitimate process image and replacing it with malicous code. It is mainly used by malware to replace the code of a running, trusted program with its own, making it very difficult to detect. Jan 24, 2024 · The article will not go into deep details about the basic process hollowing process since there are a lot of articles which explains better the technic. Điểm qua quy trình tạo một Process thông qua API CreateProcess ta có : Tạo Memory Space cho Process mới; Phân bổ stack cùng với "Thread Environment Block" và "Process Environment Block" Loads DLL hoặc EXE vào bộ nhớ Oct 9, 2017 · A technique used by malware author to evade defenses and detection analysis of malicious processes execution Process hollowing is a technique used by malware in which a legitimate process is loaded on the system solely to act as a container for hostile code. This victim process is created in a suspended state. RunPE) is probably the oldest, and the most popular process impersonation technique (it allows to run a malicious executable under the cover of a benign process). exe -o shellcode. exe shellcode for testing purposes and we will also see that the calc. Feb 2, 2025 · In conclusion, process hollowing represents a sophisticated threat to system security, leveraging legitimate system functions to evade detection and execute malicious code. The term “process hollowing” refers to the method of hollowing out the memory space of a legitimate process and replacing it with malicious code. This is Part 3 of the series. - ivkin25/Process-Hollowing Process Hollowing的MITRE ATT&CK描述： 通过上面的描述，我们初步了解了如何定义Process Hollowing，以及这种攻击的工作方式。但是，我们还需要更多上下文来创建可操作的检测方式。在MITRE的页面上，有一个“检测与参考”部分。 Mar 16, 2021 · the method comprises detecting a process starting on the user device, preparing the process to monitor Application Programming Interface (API) calls between the process and an operating system of the user device, determining whether the process is associated with a process hollowing intrusion based on information associated with the process and/or the API calls, and executing security policies . Following a webinar hosted by my colleague Justin Seitz two weeks ago, we discuss here of the detection of process hollowing, and how this capability may help in detecting ongoing cyber attacks. First, the executable creates a child process by cloning itself. Process hollowing is yet another tool in the kit of those who seek to hide the presence of a process. The process hollowing technique involves several key steps. exe process runs under a SYSTEM integrity level Sep 23, 2020 · With the hollowing process complete and code injection/copying done, the sample now reset the instruction pointer of the suspended process calc. The first stage involves creating a new instance of a legitimate process, such as svchost. במימוש הגנרי תתבצע קריאה ל – Windows API Functions מסוימות שעתה נסקור. \n. This technique has been increasingly used by attackers to evade detection and maintain persistence on compromised systems. ; Allocate memory in the new process with VirtualAllocEx() ensuring the memory region Feb 7, 2025 · GOO is a malware dropper that uses the process hollowing technique to abuse the standard Windows executable RegSvcs. jicg vnkm yqttamhk qpkwhf kvkyto tcmbjvu thj yxztgc csre jqnogs ahtzw fpr dfhly ehtw zma