AMD has divulged details about a chipset driver vulnerability that can allow non-privileged users to read and dump some types of memory pages in Windows. This technique allows an attacker to steal passwords or enable other types of attacks, including circumventing standard KASLR exploitation (aka Spectre and Meltdown) mitigations (via TheRecord).
Word of the bug came as part of a coordinated disclosure with Kyriakos Economou, a security researcher and co-founder of ZeroPeril, who exploited the vulnerability to download several gigabytes of sensitive data from impacted AMD platforms — but as a non-admin user. AMD has prepared mitigations that can be downloaded either as part of its latest chipset drivers or by using Windows Update to update the AMD PSP driver (details of how to update are below).
AMD originally issued the patch several weeks ago, but without disclosing which vulnerabilities were addressed. This new disclosure answers those questions.
The security researcher first discovered the flaw with Ryzen 2000- and 3000-series platforms, but AMD initially listed only Ryzen 1000 and older chips in its advisory. The researcher noted the discrepancy in his report, and we followed up with AMD about the issue. AMD has since updated the page with a full list of impacted platforms that spans its entire modern consumer processor lineup as well as many older models (list below).