Insecure Despite Proven Updated: Extracting the Root VCEK Seed on EPYC Milan via a Software-Only Attack

Computer Science > Cryptography and Security [Submitted on 13 May 2026] Insecure Despite Proven Updated: Extracting the Root VCEK Seed on EPYC Milan via a Software-Only Attack Muyan Shen, Yu Qin In the official whitepaper of Secure Encrypted Virtualization with Secure Nested Paging (SEV-SNP), AMD explicitly emphasizes the capability to prevent Trusted Computing Base (TCB) rollback attacks. Cryptographically, this is realized by signing attestation reports with the Versioned Chip Endorsement Key (VCEK), which is derived by incorporating the TCB version into the hardware root seed. In this architecture, safeguarding the hardware root seed is the ultimate line of defense. However, our research reveals that this protection is insufficient on EPYC Milan by presenting a software-only exploit. Specifically, we firstly introduce MilanLaunchy attack, an exploit that achieves code execution on the AMD secure processor. Building on this foundation, we develop the BadFuse attack, which extracts the hardware root seed by exploiting a lack of write restrictions in the fuse controller. This end-to-end attack chain enables an adversary to forge valid attestation reports for any firmware version, thereby effectively undermining the security model of SEV-SNP. Subjects: Cryptography and Security (cs.CR) Cite as: arXiv:2605.12990 [cs.CR]   (or arXiv:2605.12990v1 [cs.CR] for this version)   https://doi.org/10.48550/arXiv.2605.12990 Focus to learn more Submission history From: Muyan Shen [view email] [v1] Wed, 13 May 2026 04:40:23 UTC (294 KB) Access Paper: HTML (experimental) view license Current browse context: cs.CR < prev   |   next > new | recent | 2026-05 Change to browse by: cs References & Citations NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)