Ubuntu kernel notices patch AMD SEV-SNP memory flaw
First merged summary.
Ubuntu’s November 2026 kernel notices fix CVE-2023-20585 and other flaws; exploitation is not stated.
Ubuntu published Linux kernel security notices from 10 to 13 November 2026 for Azure, generic, NVIDIA, HWE and Tegra kernels. The notices describe CVE-2023-20585, in which some AMD processors skip Reverse Map Table checks when the IOMMU accesses certain host buffers. A local attacker who already has hypervisor access could trigger an out-of-bounds condition and compromise SEV-SNP guest memory integrity. The updates also correct flaws in USB Gadget, memory management, NVDIMM, networking and other subsystems. USN-9066-1 additionally describes an Arm broadcast TLB issue. The snippets give no fixed package versions and state no exploitation.
- CVE-2023-20585 needs local hypervisor access to affect SEV-SNP guest memory integrity.
- Notices include USN-9024-1, USN-9025-1, USN-9026-1, USN-9040-1, USN-9043-1, USN-9066-1 and USN-9091-1.
- Other fixes cover USB Gadget, memory management, NVDIMM, networking and several architectures.
- USN-9066-1 also describes an Arm TLB invalidation issue that can allow writes after revocation.
- Snippets omit fixed package versions and do not state exploitation.
Timeline
dated events in the reporting · oldest first- Nov 10, 2026Ubuntu publishes USN-9024-1, USN-9025-1 and Azure USN-9026-1. · Ubuntu Security Notices
- Nov 11, 2026Ubuntu publishes Azure CVM, Low Latency NVIDIA and NVIDIA kernel notices. · Ubuntu Security Notices
- Nov 12, 2026USN-9066-1 covers CVE-2023-20585 and an Arm TLB issue. · Ubuntu Security Notices
- Nov 13, 2026USN-9091-1 covers the AMD flaw for NVIDIA Tegra kernels. · Ubuntu Security Notices
What each outlet adds
beyond the shared facts- Ubuntu Security Notices (USN-9026-1)Names the Azure kernel and lists Handshake API and ARM32 among fixes.
- Ubuntu Security Notices (USN-9039-1)Azure CVM notice names architectures and drivers but lists no CVEs.
- Ubuntu Security Notices (USN-9043-1)NVIDIA notice adds MIPS, OpenRISC and other architectures to the fix list.
- Ubuntu Security Notices (USN-9066-1)Adds an Arm broadcast TLB invalidation issue on HWE kernels.
- Ubuntu Security Notices (USN-9091-1)Extends the same AMD flaw notice to NVIDIA Tegra kernels.
- CVEs
- CVE-2023-20585
Coverage
oldest first · one row per article · UTC- · 4d ago
Ubuntu Security NoticesFirst report
Ubuntu fixes Linux kernel (Azure) flaws, including AMD SEV-SNP issue
A local attacker with hypervisor access could break SEV-SNP guest memory integrity via CVE-2023-20585; other kernel subsystems are also patched.
- · 4d ago
Ubuntu kernel notice covers AMD SEV-SNP flaw CVE-2023-20585
A local attacker with hypervisor access could corrupt SEV-SNP guest memory; the same update also fixes other kernel flaws.
- · 4d ago
Ubuntu patches Linux kernel flaws, including AMD SEV-SNP issue
A local attacker with hypervisor access could use CVE-2023-20585 to corrupt SEV-SNP guest memory integrity.
- · 3d ago
Ubuntu patches Linux kernel flaws in Azure CVM images
USN-9039-1 says an attacker could possibly use flaws in multiple kernel subsystems to compromise the system.
- · 3d ago
Ubuntu kernel notice fixes AMD SEV-SNP RMP check flaw
A local attacker with hypervisor access could compromise SEV-SNP guest memory integrity.
- · 3d ago
Ubuntu kernel (NVIDIA) update fixes AMD SEV-SNP flaw CVE-2023-20585
A local attacker with hypervisor access could trigger an out-of-bounds condition and alter SEV-SNP guest memory.
- · 1d ago
Ubuntu kernel HWE flaws affect AMD SEV-SNP and Arm TLB checks
USN-9066-1 covers a local hypervisor RMP flaw (CVE-2023-20585) and an Arm TLB invalidation issue; the notice text is cut off.
- · 1d ago
Ubuntu patches NVIDIA Tegra kernel, including AMD SEV-SNP flaw
CVE-2023-20585 can let a local hypervisor attacker corrupt SEV-SNP guest memory; other kernel fixes are only partly listed.
Vulnerabilities in this story
All| CVE | Vulnerability | CVSS | EPSS | Signals | Published |
|---|---|---|---|---|---|
| CVE-2023-20585 | Insufficient checks of the RMP on host buffer access in IOMMU may allow an attacker with privileges and a compromised hypervisor to trigger an out of bounds… | 5.6 | <1% |