Vigil@nce: Linux kernel, privilege elevation via VMI
October 2008 by Vigil@nce
A local attacker in a virtual machine can create a denial of service or elevate his privileges.
Consequences: privileged access/rights, denial of service of computer
Provenance: user account
Means of attack: no proof of concept, no attack
Ability of attacker: expert (4/4)
Confidence: confirmed by the editor (5/5)
Diffusion of the vulnerable configuration: high (3/3)
Creation date: 06/10/2008
The VMI (Virtual Machine Interface) is used for communication between the guest system and the hypervisor.
The LDT (Local Descriptor Table) contains information about memory segments of the process. The IDT (Interrupt Descriptor Table) is used to manage interruptions.
The vmi_write_ldt_entry() function of the arch/x86/kernel/vmi_32.c file uses write_idt_entry() instead of write_ldt_entry(), which corrupts the IDT.
A local attacker, in a guest system, can thus create a denial of service and eventually execute code.
Identifiers: BID-31565, CVE-2008-4410, VIGILANCE-VUL-8149