Multiple security vulnerabilities were discovered in the Linux kernel for the Google Cloud Platform (linux-gcp-6.8), including a critical flaw named EntrySign affecting some AMD Zen processors. EntrySign involves improper verification of CPU microcode signatures, potentially allowing a privileged attacker to load malicious microcode, leading to loss of system integrity and confidentiality. Numerous other vulnerabilities affect a wide range of kernel subsystems and drivers. These issues could be exploited to compromise affected systems. A security update fixing these vulnerabilities is available and should be applied promptly.