Hackers are selling malware online which can be use to attack a vulnerability on popular webserver administrative tool Parallels Plesk Panel.
Brian Krebs, respected ex-Washington Post journalist and security blogger of krebsonsecurity.com, has stated that “Hackers in the criminal underground are selling an exploit that extracts the master password needed to control Parallels’ Plesk Panel”.
The malware is spreading rapidly and is currently ranked 4 in the world for online threats. With a noticeable spike in detection 0n July 18, Parallels Plesk Panel Compromise was detected on servers in 153 countries in July. AVG reports that there are currently 6,331 websites in 34 countries which host the malware.
On ZDNet, Michael Lee raise the question whether this is the result of hacker capitalising on an earlier Exploit (repaired in February) or if this ” Zero Day” Exploit is a new development.
IMPACTED PLESK VERSIONS
Parallels Plesk Panel 9.5x and 10 include this vulnerability (no prior versions have that component). Parallels Small Business Panel 10.2 is also affected.
OVERVIEW OF THE VULNERABILITY AND EXPLOIT
A flaw in the popular ProFTPD FTP server potentially allows unauthenticated attackers to compromise a server. The problem is caused by a buffer overflow in the pr_netio_telnet_gets() function for evaluating TELNET IAC sequences.
ProFTPD bug report: http://bugs.proftpd.org/show_bug.cgi?id=3521
DETAILS ON THE VULNERABILITY AND EXPLOIT
ProFTPD is capable of processing TELNET IAC sequences on port 21; the sequences enable or disable certain options not supported by the Telnet or FTP protocol itself. The buffer overflow allows attackers to write arbitrary code to the application’s stack and launch it. Updating to version 1.3.3c of ProFTPD solves the problem. The update also fixes a directory traversal vulnerability which can only be exploited if the “mod_site_misc” module is loaded. This flaw could allow attackers with write privileges to leave their permitted path and delete directories or create symbolic links outside of the path. The module is not loaded or compiled by default.