USN-8603-1: Linux kernel (Azure) vulnerabilities
It was discovered that some AMD processors did not properly clear data in the floating point divider unit during speculative execution. A local attacker could use this to expose sensitive information. (CVE-2025-54505) It was discovered that some AMD Zen 2 processors did not properly isolate shared resources in the operation cache. A local attacker could possibly use this issue to corrupt instructions executed at a higher privilege level, resulting in privilege escalation. (CVE-2025-54518) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - x86 platform drivers; - PSP security protocol; - ARM32 architecture; - ARM64 architecture; - MIPS architecture; - PowerPC architecture; - RISC-V architecture; - S390 architecture; - User-Mode Linux (UML); - x86 architecture; - Block layer subsystem; - Cryptographic API; - Intel NPU Driver; - Compute Acceleration Framework; - ACPI drivers; - Auxiliary display drivers; - Drivers core; - DRBD Distributed Replicated Block Device drivers; - Rados block device (RBD) driver; - Ublk userspace block driver; - Compressed RAM block device driver; - Bluetooth drivers; - Bus devices; - Character device driver; - TPM device driver; - Clock framework and drivers; - CPU frequency scaling framework; - Hardware crypto device drivers; - Buffer Sharing and Synchronization framework; - DPLL subsystem; - EDAC drivers; - Arm Firmware Framework for ARMv8-A(FFA); - EFI core; - FWCTL subsystem; - GPIO subsystem; - GPU drivers; - Greybus drivers; - HID subsystem; - Microsoft Hyper-V drivers; - Hardware monitoring drivers; - I2C subsystem; - I3C subsystem; - IIO ADC drivers; - IIO subsystem; - InfiniBand drivers; - Input Device core drivers; - IOMMU subsystem; - LED subsystem; - Mailbox framework; - Multiple devices driver; - Media drivers; - NVIDIA Tegra memory controller driver; - IBM Advanced System Management driver; - MTD blo
CSIRTS triage
- What
- Multiple vulnerabilities could allow local attackers to expose sensitive information or escalate privileges.
- Who is affected
- Local users of the Linux kernel on affected AMD processors.
- Urgency
- Remediation is high urgency due to the potential for privilege escalation and system compromise.
- Action
- Update the Linux kernel to the latest version.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://ubuntu.com/security/notices/USN-8603-1
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Low exploitation riskCVE-2025-545050.19% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 9% of all scored CVEs.
- Low exploitation riskCVE-2025-545180.26% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 17% of all scored CVEs.
- Low exploitation riskCVE-2026-315320.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
- Low exploitation riskCVE-2026-315740.11% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 1% of all scored CVEs.
- Low exploitation riskCVE-2026-315750.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all scored CVEs.
- Low exploitation riskCVE-2026-315760.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
- Low exploitation riskCVE-2026-315770.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
- Low exploitation riskCVE-2026-315780.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
- Low exploitation riskCVE-2026-315790.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all scored CVEs.
- Low exploitation riskCVE-2026-315800.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
Referenced CVEs
+982 more CVEs referenced in this advisory.
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
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