Command-line parameters are some of the most reliable telemetry for detecting malicious use of Rundll32, since adversaries often need to pass command-line arguments for Rundll32 to execute. Eight of our top 10 detection analytics for Rundll32 include a command-line component. Capturing command-line activity will capture the both name of the DLL that was launched by rundll32.exe and any additional command-line arguments.
name rundll32.exe comsvcs.dll file version not loaded
Download File: https://urluso.com/2vKOHq
Consider monitoring for instances of rundll32.exe running Windows native DLLs that have export functionalities that adversaries commonly leverage for executing malicious code and evading defensive controls. The following pseudo-analytic applies specifically to adversaries who use the MiniDump export functionality of comsvcs.dll to dump the contents of LSASS, but this logic could be adapted to detect other malicious activity as well.
In this short article, you will discover detailed file information, steps for troubleshooting DLL file problems with comsvcs.dll, and list of free downloads for every version that exists in our comprehensive file directory.
Comsvcs.dll is considered a type of Dynamic Link Library (DLL) file. Dynamic Link Library files, like comsvcs.dll, are essentially a "guide book" that stores information and instructions for executable (EXE) files - like HelpPane.exe - to follow. These files were created so that multiple programs (eg. Microsoft Office Access 2010) could share the same comsvcs.dll file, saving valuable memory allocation, therefore making your computer run more efficiently.
Unfortunately, what makes DLL files so convenient and efficient, also makes them extremely vulnerable to problems. If something happens to a shared DLL file, either it goes missing or gets corrupted in some way, it can generate a "runtime" error message. Runtime is pretty self-explanatory; it means that these errors are triggered when comsvcs.dll is attempted to be loaded either when Microsoft Office Access 2010 is starting up, or in some cases already running. Some of the most common comsvcs.dll errors include:
Your comsvcs.dll file could be missing due to accidental deletion, uninstalled as a shared file of another program (shared with Microsoft Office Access 2010), or deleted by a malware infection. Furthermore, comsvcs.dll file corruption could be caused from a power outage when loading Microsoft Office Access 2010, system crash while loading comsvcs.dll, bad sectors on your storage media (usually your primary hard drive), or quite commonly, a malware infection. Thus, it's critical to make sure your anti-virus is kept up-to-date and scanning regularly.
If none of the previous three troubleshooting steps have resolved your issue, you can try a more aggressive approach (Note: Not recommended for amateur PC users) by downloading and replacing your appropriate comsvcs.dll file version. We maintain a comprehensive database of 100% malware-free comsvcs.dll files for every applicable version of Microsoft Office Access 2010. Please follow the steps below to download and properly replace you file:
CAUTION : We strongly advise against downloading and copying comsvcs.dll to your appropriate Windows system directory. Microsoft typically does not release Microsoft Office Access 2010 DLL files for download because they are bundled together inside of a software installer. The installer's task is to ensure that all correct verifications have been made before installing and placing comsvcs.dll and all other DLL files for Microsoft Office Access 2010. An incorrectly installed DLL file may create system instability and could cause your program or operating system to stop functioning altogether. Proceed with caution.
However, thanks to the Cybereason Defense Platform, we could examine the history, all loaded modules and all other relevant information and also visualize the processes tree to notice that rundll32.exe is the parent of cmd.exe:
We have seen that rundll32.exe is a powerful asset for adversaries to proxy execution of arbitrary and malicious code. This binary has another ace in the hole, it could leverage comsvcs.dll (a Microsoft-signed DLL) which exports a function called MiniDumpW that rely on MiniDumpWriteDump to dump lsass.exe (Local Security Authority Subsystem Service) process memory to retrieve credentials.
Adversaries may abuse rundll32.exe to proxy execution of malicious code. Using rundll32.exe, vice executing directly (i.e. Shared Modules), may avoid triggering security tools that may not monitor execution of the rundll32.exe process because of allowlists or false positives from normal operations. Rundll32.exe is commonly associated with executing DLL payloads (ex: rundll32.exe DLLname, DLLfunction).
Rundll32.exe can also be used to execute Control Panel Item files (.cpl) through the undocumented shell32.dll functions Control_RunDLL and Control_RunDLLAsUser. Double-clicking a .cpl file also causes rundll32.exe to execute. [1]
Adversaries may also attempt to obscure malicious code from analysis by abusing the manner in which rundll32.exe loads DLL function names. As part of Windows compatibility support for various character sets, rundll32.exe will first check for wide/Unicode then ANSI character-supported functions before loading the specified function (e.g., given the command rundll32.exe ExampleDLL.dll, ExampleFunction, rundll32.exe would first attempt to execute ExampleFunctionW, or failing that ExampleFunctionA, before loading ExampleFunction). Adversaries may therefore obscure malicious code by creating multiple identical exported function names and appending W and/or A to harmless ones.[3][4] DLL functions can also be exported and executed by an ordinal number (ex: rundll32.exe file.dll,#1).
Use process monitoring to monitor the execution and arguments of rundll32.exe. Compare recent invocations of rundll32.exe with prior history of known good arguments and loaded DLLs to determine anomalous and potentially adversarial activity.
According to our database, the comsvcs.dll file is part of the Microsoft Windows Operating System product, so the comsvcs.dll file may get onto your computer through the installation of Microsoft Windows Operating System.
We don't advise to download the comsvcs.dll file and copy it to the Windows system directory. The software's creators almost never circulate the DLL files, they are always part of an installation set. It's the installation set's task to perform the sufficient verifications before the installation. An incorrectly installed DLL file may cause the system's complete inability to function.
Arguably, the most notorious tool in the Windows landscape for red teams and threat actors is Mimikatz, the tool used to extract usernames and passwords from LSASS. Benjamin Delpy, its creator, has thoroughly researched the authentication process in Windows, and released an open-source tool with the capability of extracting Windows credentials that are stored in the LSASS process. He does this either by reading the memory structures inside LSASS memory space or by reading a full memory dump file of LSASS.
The issue was caused by a filter driver that Cylance uses to implement LSASS memory protections by injecting CyMemDef.dll into every process. The solution identified by Tyler was to simply rename CyMemDef.dll. If the DLL file does not exist, Cylance has nothing to inject into every process, and will not be able to prevent an attacker from dumping LSASS memory ?
tstats `security_content_summariesonly` count min(_time) as firstTime max(_time) as lastTime from datamodel=Endpoint.Processes where `process_rundll32` Processes.process=*comsvcs.dll* Processes.process=*MiniDump* by Processes.userProcesses.process_nameProcesses.original_file_nameProcesses.processProcesses.dest `drop_dm_object_name(Processes)` `security_content_ctime(firstTime)` `security_content_ctime(lastTime)` `dump_lsass_via_comsvcs_dll_filter`
While these types of detections are easily bypassed by changing the name of the dump file or using tools other than procdump, they can be useful as part of a defense in depth strategy to catch lazy attackers or malware using off-the-shelf tools with default settings.
The execution phase started with that password protected zip, which after extracting would show the user an ISO file that after the user double clicks would mount like a CD or external media device on Windows and present the user with a single file named documents in the directory.
When the user double clicks or opens the lnk file, they inadvertently start a hidden file, a DLL (namr.dll) containing the Bumblebee malware loader. From there, the loader reached out to the Bumblebee C2 servers. At first, things remained fairly quiet, just C2 communications; until around 3 hours later, Bumblebee dropped a Cobalt Strike beacon named wab.exe on the beachhead host. This Cobalt Strike beacon was subsequently executed and then proceeded to inject into various other processes on the host (explorer.exe, rundll32.exe). From these injected processes, the threat actors began discovery tasks using Windows utilities like ping and tasklist.
The initial payload named BC_invoice_Report_CORP_46.iso, is an ISO image that once mounted, lures the user to open a document.lnk file which will execute the malicious DLL loader using the following command line:
The source of execution, the initiating parent process, was different on each occasion and the name of AdFind binary and the result files were different on one occasion, which could indicate multiple Threat actors accessing the network.
Detects NotPetya ransomware activity in which the extracted passwords are passed back to the main module via named pipe, the file system journal of drive C is deleted and windows eventlogs are cleared using wevtutil
The SAM (Security Account Manager) database is stored as a file on the local disk and contains information on local accounts, including the username and the hashed password. The SAM file is located in %systemroot%\system32\config\SAM and is mounted on the HKEY_LOCAL_MACHINE/SAM (HKLM/SAM) registry hive. Moreover, the password hashes can be found in %systemroot%\system32\config\SYSTEM file, and backup copies can be found in %systemroot%\repair\ directory. 2ff7e9595c
コメント