The vulnerability in the Linux kernel relates to the handling of memory pages in the SEV-guest feature. When the functions set_memory_encrypted or set_memory_decrypted fail, the caller cannot determine the failure point, resulting in pages left in an unknown encryption state. Because these pages may remain unencrypted, they are unsuitable for reuse and cannot be safely returned to the buddy allocator. The resolution explicitly leaks these pages and performs correct accounting by invoking snp_leak_pages(), preventing unsafe reuse of potentially unencrypted memory.

Pages left in an unknown encryption state may be unencrypted and thus expose sensitive data if reused improperly. This could lead to information disclosure risks within SEV-guest virtualized environments. However, the vulnerability is addressed by explicitly leaking such pages and accounting for them, preventing unsafe memory reuse.

A fix has been implemented in the Linux kernel to explicitly leak pages left in an unknown state and properly account for them using snp_leak_pages(). Users should apply the official kernel updates that include this fix. Patch status is not explicitly confirmed in the provided data; therefore, check the vendor advisory for current remediation guidance.