Insufficient or Incomplete Data Removal in Hardware Component in SEV firmware doesnt fully flush IOMMU. This can potentially lead to a loss of confidentiality and integrity in guest memory.
Weakness
The product’s data removal process does not completely delete all data and potentially sensitive information within hardware components.
Extended Description
Physical properties of hardware devices, such as remanence of magnetic media, residual charge of ROMs/RAMs, or screen burn-in may still retain sensitive data after a data removal process has taken place and power is removed. Recovering data after erasure or overwriting is possible due to a phenomenon called data remanence. For example, if the same value is written repeatedly to a memory location, the corresponding memory cells can become physically altered to a degree such that even after the original data is erased that data can still be recovered through physical characterization of the memory cells.