Real risk for VMware users
VMware users running shared folders could be vulnerable to hackers and viruses, warn security researchers.
By using certain strings in a pathname, which VMware fails to filter out, a malicious hacker can access the whole file system of the host computer.
The flaw means that a user running on a guest system could gain access to the host computer, and therefore any sensitive files stored on it.
Malicious code, including viruses and Trojans could use the same exploit, leaving devices previously thought immune from attack vulnerable.
“This discovery demonstrates that thousands of companies with virtualised systems could unknowingly be exposing critical information assets that they otherwise sought to protect,” warns a statement from Core Security Technologies, which revealed the security flaw.
The company has also released an exploit for the flaw, “enabling customers to validate that it exists, prove that can be exploited, and safely assess the consequences of an actual network intrusion.”
The exploit only works on VMware Workstation 6.0.2 and earlier, Player 2.0.2 and earlier and ACE 2.0.2 and earlier. VMware Server is not affected, because it does not use shared folders.
VMware has acknowledged the security vulnerability, and says that a fix is under development.
“Until VMware releases a patch to fix this issue, users of affected Windows-hosted VMware products should disable shared folders,” says a VMware advisory.