Security researchers at Cisco Talos say they have identified a range of serious vulnerabilities in AMD firmware that could be remotely exploited by a non-authenticated attacker, potentially giving access to VMware workstations.

Cisco Talos’s Piotr Bania reported the vulnerabilities in the AMD Radeon graphics card ATIDXX64.DLL driver to the company in early October 2019.

The first AMD driver vulnerability, CVE-2019-5183, comes with a critical CVSS score of 9.0. In a unique attack, Bania created a “specially crafted pixel shader” (a method of rendering graphical features) to exploit the bug.

The vulnerability affects AMD ATI Radeon RX 550/550 Series for VMware Workstation and could allow a remote attacker to execute arbitrary code.

VMware’s security response centre told customers today: “We wanted to make you aware of multiple AMD security issues.. these have been shown to affect VMware Workstation running on Windows.” It urged users to patch.

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Bania said: “This vulnerability can be triggered by supplying a malformed pixel shader (inside VMware guest operating system). Such attack can be triggered from VMware guest usermode. The vulnerability will be triggered in the vmware-vmx.exe process on host, or theoretically through WEBGL (remote website), leading to potential code execution (through a vtable type-confusion).

The security issues, CVE-2019-5124, CVE-2019-5146, CVE-2019-5147 and as described above, CVE-2019-5183, were tested on Radeon RX 550 /550 Series VMware Workstation 15 (15.5.0 build-14665864) with Windows 10 x64.

Users have been urged to update to upgrade to the latest version of AMD drivers (20.1.1 or later), available from the AMD website.

As ever, security teams should ensure software is patched as regularly as possibly and basic security hygiene precautions are adhered to.

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