Researchers have discovered vulnerabilities in a series of virtualisation software platforms that allow attackers to gain unauthorised access.
The holes could be exploited to achieve local privileged escalation and virtual machine escapes on software from vendors Xen, FreeBSD, Microsoft, and RedHat running on 64-bit operating systems on Intel processors.
Invisible Things Lab principle researcher Rafal Wojtczuk discovered the flaws, which he said allowed a ring3 attacker to craft a stack frame to be executed by the kernel after a general protection exception.
US CERT’s Jared Allar issued an alert stating that “the fault will be handled before the stack switch, which means the exception handler will be run at ring0 with an attacker's chosen RSP causing a privilege escalation”.
VMware and AMD processors were not affected.
Users were urged to apply vendor patches. More detail is available on the US CERT advisory.
Wojtczuk detailed the following ring3 attack steps:
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Issue: 342 | September 2015