USN-7861-3: Linux kernel vulnerabilities

USN-7861-3: Linux kernel vulnerabilities

Publication date: 13 November 2025
Overview: Several security issues were fixed in the Linux kernel.

Packages

• linux-nvidia-6.8 - Linux kernel for NVIDIA systems
• linux-oracle - Linux kernel for Oracle Cloud systems
• linux-oracle-6.8 - Linux kernel for Oracle Cloud systems

Details
Jean-Claude Graf, Sandro Rüegge, Ali Hajiabadi, and Kaveh Razavi discovered
that the Linux kernel contained insufficient branch predictor isolation
between a guest and a userspace hypervisor for certain processors. This
flaw is known as VMSCAPE. An attacker in a guest VM could possibly use this
to expose sensitive information from the host OS. (CVE-2025-40300)

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:

• HSI subsystem;
• Bluetooth subsystem;
• Timer subsystem

Update instructions
After a standard system update you need to reboot your computer to make all the necessary changes.

The problem can be corrected by updating your system to the following package versions:

24.04 LTS noble

• linux-image-6.8.0-1039-oracle – 6.8.0-1039.40
• linux-image-6.8.0-1039-oracle-64k – 6.8.0-1039.40
• linux-image-oracle-6.8 – 6.8.0-1039.40
• linux-image-oracle-64k-6.8 – 6.8.0-1039.40
• linux-image-oracle-64k-lts-24.04 – 6.8.0-1039.40
• linux-image-oracle-lts-24.04 – 6.8.0-1039.40

22.04 LTS jammy

• linux-image-6.8.0-1039-oracle – 6.8.0-1039.40~22.04.1
• linux-image-6.8.0-1039-oracle-64k – 6.8.0-1039.40~22.04.1
• linux-image-6.8.0-1042-nvidia – 6.8.0-1042.45~22.04.1
• linux-image-6.8.0-1042-nvidia-64k – 6.8.0-1042.45~22.04.1
• linux-image-nvidia-6.8 – 6.8.0-1042.45~22.04.1
• linux-image-nvidia-64k-6.8 – 6.8.0-1042.45~22.04.1
• linux-image-nvidia-64k-hwe-22.04 – 6.8.0-1042.45~22.04.1
• linux-image-nvidia-hwe-22.04 – 6.8.0-1042.45~22.04.1
• linux-image-oracle – 6.8.0-1039.40~22.04.1
• linux-image-oracle-6.8 – 6.8.0-1039.40~22.04.1
• linux-image-oracle-64k – 6.8.0-1039.40~22.04.1
• linux-image-oracle-64k-6.8 – 6.8.0-1039.40~22.04.1