Vigil@nce: Avast, privilege elevation via aavmker4.sys
March 2010 by Vigil@nce
SYNTHESIS OF THE VULNERABILITY
A local attacker can corrupt the memory of the aavmker4.sys driver, in order to generate a denial of service or to execute code.
Consequences: administrator access/rights, denial of service of computer
Provenance: user shell
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: 23/02/2010
DESCRIPTION OF THE VULNERABILITY
The Avast antivirus installs the aavmker4.sys driver on Windows systems.
This driver is reached via ioctls, whose parameters are normally checked. However, an attacker can use the 0xb2d6001c ioctl and then the 0xb2d60030 ioctl, in order to corrupt the memory.
A local attacker can therefore corrupt the memory of the aavmker4.sys driver, in order to generate a denial of service or to execute code.
Identifiers: BID-38363, CVE-2010-0705, TKADV2010-003, VIGILANCE-VUL-9470