KVM qemu-kvm "ext4_fill_flex_info()" Denial of Service

by Carol~ Moderator - 4/9/12 10:40 AM

In Reply to: VULNERABILITIES / FIXES - April 09, 2012 by Carol~ Moderator

KVM qemu-kvm "ext4_fill_flex_info()" Denial of Service Vulnerability

Release Date : 2012-04-09

Criticality level : Not critical
Impact : DoS
Where : Local system
Solution Status : Vendor Workaround

Software: KVM (Kernel-based Virtual Machine)

Description:
A vulnerability has been reported in KVM qemu-kvm, which can be exploited by malicious, local users in a guest virtual machine to cause a DoS (Denial of Service).

The vulnerability is caused due to an error within the "ext4_fill_flex_info()" function in fs/ext4/super.c when mounting a file system and can be exploited to cause a division by zero.

Solution:
Fixed in the GIT repository.

Provided and/or discovered by:
Reported by the vendor.

Original Advisory:
http://git.kernel.org/?p=virt/kvm/kvm.git;a=commit;h=d50f2ab6f050311dbf7b8f5501b25f0bf64a439b

http://secunia.com/advisories/48645/