RMPocalypse Flaw (CVE-2025-0033) Bypasses AMD SEV-SNP to Fully Compromise Encrypted VMs

A team from ETH Zurich disclosed CVE-2025-0033, a flaw dubbed RMPocalypse that undermines AMD SEV-SNP across Zen 3, Zen 4 and Zen 5 processors, allowing attackers to fully compromise encrypted VMs and void confidentiality and integrity guarantees. The researchers describe a misalignment between Trusted Memory Regions and cache coherence during SEV-SNP initialization, which lets a malicious hypervisor flush dirty cachelines to RMP memory and overwrite it.

ETH Zurich summarizes that a single 8-byte overwrite within the RMP can compromise the entire RMP, enabling attestation manipulation, read or modification of encrypted VM memory, and denial of trusted safeguards. The study notes the attack is deterministic and succeeds every time, beginning during RMP setup when the PSP configures protections before confidential VMs start.

According to the ETH Zurich study, a compromised RMP lets attackers tamper with attestation hashes and debug flags, effectively granting full control over confidential VMs, with 100% success in their case studies. Following disclosure, AMD acknowledged the flaw and released firmware mitigations.