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遭遇黑客软件

昨晚突然发现电脑变慢，ps一看有好多以www用户名的进程，我可没有这个用户啊，再看那些进程，一堆scan和一个httpd等，真是可疑。

然后去/proc/查看，那些文件的可执行文件都位于/tmp/.a，里面除了这个scanner和httpd外，还有bruteforce和一个弱密码字典，以及一些扫描的log。 哇，中招了！

于是赶紧杀进程，然后想删掉这些文件，却总是报Segmentation fault, 之后又试了几个命令，也是报这个错，我看了一下/bin， 啊，原来很多命令的文件都被修改了。 于是重启，发现启动过程中都是Segmentation fault, 一下子懵住了。 当时太困了，不知所措，只好关掉等今天解决。

实在是不想重装，于是试图恢复，首先用live cd启动，把/bin的那些文件拷过去一份，然后搜了下/sbin,/usr/bin等重要文件夹，没有被改动的样子（这里/bin,/sbin,/usr/bin都是硬盘上的而不是live cd上的）， 之后，用chroot和aptitude重装了一下coreutils,为了保险，把一些*utils都重装了一下。

然后重启，似乎是正常了，松了一口气。但是还是要观望一段时间，看有没有什么遗留的。

现在想一下，根据那个文件夹里的log和字典文件推断，那个scanner是破解ssh里高权限用户的密码，然后一看我这里的root密码，天啊，原来是个弱密码，我才想起来当时装MySQL时图省事弄的，结果现在忘了。。真是敲响了警钟。

另外上网搜了一下相关资料，除了看到一个人跟我有类似情况外，没有别的有用的信息，看来这个东西还是挺新的。

现在赶紧把ssh的root登录关掉。

总之是第一次有这种经历，万幸阿，那个程序没给我rm -rf /, 我作业还没写完呢。。
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