Processor vulnerability
CVE-2021-46744
A malicious hypervisor can infer data in an SEV guest by watching how its ciphertext changes over time; AMD answers with guidance for software.
- Name
- Ciphertext side channels on SEV
- Vulnerability
- AMD SEV, SEV-ES and SEV-SNP
- Kind
- Other
- CVE published
- 2022-05-11 CVE record
- Advisories
- AMD-SB-1033
A hypervisor can read the ciphertext of an SEV guest’s memory,
though not the plaintext, and changes in that ciphertext over time
give away data values. Researchers from the University of Luebeck
and The Ohio State University turned this into attacks on
cryptographic code in SEV-SNP guests (IEEE S&P 2022). AMD’s bulletin
treats it as a matter for the software in the guest and points to
its technical guidance on ciphertext visibility under SEV.What the sources say of each microarchitecture.
Affected processors
3 of the 3 microarchitectures listed are affected in all or some of their models.
Mitigations
- Programs: AMD's technical guidance for mitigating the effects of ciphertext visibility under SEV, applied to the software in the guest. Source.
Related CVEs
- CVE-2019-9836 SEV key recovery through invalid curve points
- CVE-2020-12966 Ciphertext side channel on SEV-ES register state
- CVE-2020-12967 Unprotected nested page tables of SEV guests
- CVE-2021-26311 Rearranged guest memory that attestation misses
- CVE-2021-26320 SEND_START signing key check
- CVE-2021-26321 ID command validation
- CVE-2021-26323 SEV commands while SNP is active
- CVE-2021-26324 SEV-ES TMR and SNP guests
- CVE-2021-26325 SNP_GUEST_REQUEST input
- CVE-2021-26326 VM_HSAVE_PA at SNP_INIT
- CVE-2021-26327 SNP guest context validation
- CVE-2021-26328 CPU mode at SNP_INIT
- CVE-2021-26332 SEV-ES TMR in MMIO space
- CVE-2021-26340 TLB poisoning of SEV guests
- CVE-2021-26342 Missed TLB flush after a new VMCB
- CVE-2021-26349 Report ID of an imported SNP guest
- CVE-2021-26396 Secure Processor I/O address mapping
- CVE-2021-26402 Mailbox writes into SMM or SEV-ES memory
- CVE-2021-26403 Launch secret disclosure
- CVE-2021-26404 SEV firmware scratch buffer leak
- CVE-2021-26406 OCA certificate parsing
- CVE-2021-26408 Curve points in legacy SEV migration
- CVE-2021-26409 RMP corruption through SEV-ES
- CVE-2021-46768 Bootloader reads from SEV firmware input
- CVE-2022-23813 SNP policy in Secure Processor and SMU interfaces
- CVE-2022-23814 Addresses passed to BIOS commands
- CVE-2022-23818 VM_HSAVE_PA input validation
- CVE-2022-23830 SMM configuration under SNP
- CVE-2023-20519 Use after free of an SNP guest context page
- CVE-2023-20566 Secure Processor address checks under SNP
- CVE-2023-20573 Suppressed debug exceptions in SNP guests
- CVE-2023-20575 Power side channel on SEV guests
- CVE-2023-20581 IOMMU access control bypasses RMP checks
- CVE-2023-20582 Invalid nested page table entries in the IOMMU
- CVE-2023-20584 IOMMU device table faults bypass RMP checks
- CVE-2023-20585 RMP checks on IOMMU host buffer access
- CVE-2023-20592 INVD and guest memory integrity
- CVE-2023-31346 Uninitialized SEV firmware memory
- CVE-2023-31347 Secure TSC bug
- CVE-2023-31351 IOMMU access to guest private memory
- CVE-2023-31352 SEV firmware reads of unencrypted memory
- CVE-2023-31355 UMC seed overwrite in SNP firmware
- CVE-2023-31356 Incomplete memory cleanup in SEV firmware
- CVE-2024-21944 Memory aliasing through DIMM SPD data
- CVE-2024-21953 IOMMU register reconfiguration
- CVE-2024-21977 RDRAND entropy after a microcode load
- CVE-2024-21978 SEV-SNP input validation
- CVE-2024-21980 SNP firmware write restrictions
- CVE-2024-36331 Uninitialized cache memory
- CVE-2025-0012 Overlap of the segmented RMP and SMM memory
- CVE-2025-0029 Dropped guest DMA writes
- CVE-2025-0031 SINGLE_SOCKET policy after migration
- CVE-2025-0033 RMP corruption during SNP initialization
- CVE-2025-29934 Stale TLB entries in SEV-SNP guests
- CVE-2025-29939 RMP writes during SNP initialization
- CVE-2025-29943 SEV-SNP guest stack pointer corruption
- CVE-2025-29946 Incomplete IOMMU flush
- CVE-2025-29948 RMP protection bypass in SEV firmware
- CVE-2025-29952 RMP-covered memory corruption
- CVE-2025-48509 I/O memory misidentified at RMP initialization
- CVE-2025-48514 SEV-ES guest attacking an SNP guest
- CVE-2025-48517 SEV-ES guest with an SNP ASID
- CVE-2025-52536 SEV firmware downgrade
- CVE-2025-54510 MMIO routing lock in Secure Processor firmware
- CVE-2025-61971 MMIO routing through NBIO registers
- CVE-2025-61972 SMN access through NBIO registers