USN-8665-1: Linux kernel (Raspberry Pi) 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) It was discovered that some AMD Zen 5 processors supporting RDSEED instruction did not properly handle entropy, potentially resulting in the consumption of insufficiently random values. A local attacker could possibly use this issue to influence the values returned by the RDSEED instruction causing loss of confidentiality and integrity. (CVE-2025-62626) 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: - ARM64 architecture; - RISC-V architecture; - S390 architecture; - x86 architecture; - Block layer subsystem; - Cryptographic API; - Compute Acceleration Framework; - ACPI drivers; - Serial ATA and Parallel ATA drivers; - Drivers core; - Power management core; - DRBD Distributed Replicated Block Device drivers; - Rados block device (RBD) driver; - Compressed RAM block device driver; - Bluetooth drivers; - Bus devices; - Character device driver; - Clock framework and drivers; - Data acquisition framework and drivers; - Counter interface drivers; - CPU frequency scaling framework; - Hardware crypto device drivers; - CXL (Compute Express Link) drivers; - DMA engine subsystem; - EDAC drivers; - EFI core; - GPU drivers; - Greybus drivers; - HID subsystem; - Hardware monitoring drivers; - I2C subsystem; - IIO ADC drivers; - IIO subsystem; - InfiniBand drivers; - Input Device (Miscellaneous) drivers; - IRQ chip drivers; - LED subsystem; - Mailbox framework; - Mu
CSIRTS triage
- What
- Microarchitectural vulnerabilities in AMD processors and Linux kernel flaws affecting floating-point divider, operation cache isolation, and RDSEED entropy handling.
- Who is affected
- Raspberry Pi systems and those running affected AMD processors with vulnerable Linux kernels.
- Urgency
- Moderate; side-channel and privilege escalation vectors, mostly local exploitation required.
- Action
- Apply USN-8665-1 kernel security update for Raspberry Pi.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch Linux kernel (Raspberry Pi)
Get an email when a new Linux kernel (Raspberry Pi) advisory drops — max one per day, one-click unsubscribe.
Details
Original advisory: https://ubuntu.com/security/notices/USN-8665-1
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 EPSS-scored CVEs.
- Low exploitation riskCVE-2025-545180.29% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 21% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-626260.17% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 7% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-217090.20% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 10% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-221160.19% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 9% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-384260.16% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-397640.17% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-401350.55% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 44% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-401500.25% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 16% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-681750.15% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 5% of all EPSS-scored CVEs.
Referenced CVEs
+864 more CVEs referenced in this advisory.
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- unknownUSN-8666-2: Linux kernel (Azure) vulnerabilitiesubuntu
- high[UPDATE] [high] Linux Kernel: Multiple vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- high[UPDATE] [high] Linux Kernel: Multiple Vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple vulnerabilitiescert-bund
- high[UPDATE] [high] Linux Kernel: Multiple Vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- highexploited[UPDATE] [high] Linux Kernel: Multiple vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
More from Ubuntu Security Notices
- unknownUSN-8659-4: Linux kernel (Oracle) vulnerability2026-08-26
- unknownUSN-8666-2: Linux kernel (Azure) vulnerabilities2026-08-25
- unknownUSN-8630-5: Linux kernel (Raspberry Pi) vulnerabilities2026-08-25
- unknownUSN-8658-3: Linux kernel vulnerabilities2026-08-25
- unknownUSN-8643-4: Linux kernel vulnerabilities2026-08-25