Malware authors on Christmas day left dubious “gift” packages in e-mailboxes across the Internet. Fresh attacks, which took advantage of old Internet Explorer bugs, as well as new versions of the Santy worm fouled the holidays for some Windows users and PHP server admins.
A posting on the Full Disclosure mailing list described a new attack that can proceed without user intervention. Called “Microsoft Internet Explorer Full Remote Compromise w/o User Intervention,” the exploit is based on old vulnerabilities in Internet Explorer in Windows XP SP2 (Service Pack 2).
The provided analysis of the attack mentions two targets in SP2: the Help ActiveX control related topics zone security bypass vulnerability and the Help ActiveX control related topics cross site scripting vulnerability.
The attack is described in detail and results in an arbitrary file being placed in the users startup folder where it will be when the user restarts the system. According to the analysis, the attack does not lend itself to inclusion in a worm, but could be effectively used by spyware or adware to compromise a system.
According to the post, the exploit was released by Michael Evanchik and Paul from Greyhats Security, to spur Microsoft Corp. to secure Windows and the Internet Explorer browser more quickly. The message from Paul, suggested Windows users switch to the Mozilla projects FireFox browser to improve security.
“Microsoft was able to reproduce the issue and has agreed that the severity is indeed critical. Because the vulnerabilities (3 in total, each based on different technologies) have been known and unpatched for quite some time, we have decided to release the information on this exploit in hopes that in the future Microsoft will work faster towards patching vulnerabilities that we security researchers disclose to them,” the posting said.
Microsoft was unavailable for comment.
Meanwhile, as the Santy.A worm attack from last week is subsiding, security researchers warned that the next generation of the worm is riding on America Online and Yahoo Inc. search services. The earlier version used the Google Inc. search engine. Santy.B finds phpBB-based servers to attack by searching for “viewtopic.php” and “using the AOL or Yahoo search engine to generate a list of possible infection targets,” Symantec Corp. analysts said.
Santy.B exploits the same server-side vulnerability as Version A—PHPBB Remote URLDecode Input Validation Vulnerability. The worm overwrites all .htm, .php, .asp, .shtm, .jsp, and .phtm files with a defacement message.
Security alerts urged administrators to upgrade to phpBB Version 2.0.11, which fixes the vulnerability. However, one post to the Bugtraq security mailing list warned that Version 2.0.11 is also affected.
The new versions appear to be more versatile and deadly than Santy.A, security insiders observed. Early reports on e-mail lists said that Santy.B installs a backdoor server and a remote control IRC tool on affected machines. The exploit may not be limited to phpBB sites but may also attack other PHP sites with a general script-injection technique.