1. Ubuntu Security Notices
  2. USN-8184-1

USN-8184-1: Linux kernel (Real-time) vulnerabilities

Publication date

17 April 2026

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

Details

Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)

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:

  • MIPS architecture;
  • PowerPC architecture;
  • x86 architecture;
  • Block layer subsystem;
  • Cryptographic API;
  • ACPI drivers;
  • Network block device driver;
  • Bluetooth drivers;
  • Character device driver;
  • TPM device driver;
  • Clock framework and drivers;
  • Data acquisition framework...

Josh Eads, Kristoffer Janke, Eduardo Vela Nava, Tavis Ormandy, and Matteo
Rizzo discovered that some AMD Zen processors did not properly verify the
signature of CPU microcode. This flaw is known as EntrySign. A privileged
attacker could possibly use this issue to cause load malicious CPU
microcode causing loss of integrity and confidentiality.
(CVE-2024-36347)

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:

  • MIPS architecture;
  • PowerPC architecture;
  • x86 architecture;
  • Block layer subsystem;
  • Cryptographic API;
  • ACPI drivers;
  • Network block device driver;
  • Bluetooth drivers;
  • Character device driver;
  • TPM device driver;
  • Clock framework and drivers;
  • Data acquisition framework and drivers;
  • Hardware crypto device drivers;
  • GPU drivers;
  • Hardware monitoring drivers;
  • InfiniBand drivers;
  • Input Device core drivers;
  • IOMMU subsystem;
  • IRQ chip drivers;
  • Macintosh device drivers;
  • Multiple devices driver;
  • Media drivers;
  • Network drivers;
  • Mellanox network drivers;
  • STMicroelectronics network drivers;
  • Ethernet team driver;
  • MediaTek network drivers;
  • NVME drivers;
  • PA-RISC drivers;
  • Chrome hardware platform drivers;
  • x86 platform drivers;
  • Voltage and Current Regulator drivers;
  • SCSI subsystem;
  • SPI subsystem;
  • Media Oriented Systems Transport (MOST) driver;
  • Realtek RTL8723BS SDIO drivers;
  • TCM subsystem;
  • USB Host Controller drivers;
  • USB Type-C Connector System Software Interface driver;
  • Backlight driver;
  • Watchdog drivers;
  • BFS file system;
  • BTRFS file system;
  • Ext4 file system;
  • F2FS file system;
  • FUSE (File system in Userspace);
  • HFS+ file system;
  • File systems infrastructure;
  • Journaling layer for block devices (JBD2);
  • Network file system (NFS) client;
  • File system notification infrastructure;
  • NTFS3 file system;
  • OCFS2 file system;
  • SMB network file system;
  • BPF subsystem;
  • Ethernet bridge;
  • io_uring subsystem;
  • Locking primitives;
  • Scheduler infrastructure;
  • Shadow Call Stack mechanism;
  • Tracing infrastructure;
  • Memory management;
  • CAIF protocol;
  • Ceph Core library;
  • Networking core;
  • Ethtool driver;
  • Handshake API;
  • HSR network protocol;
  • IPv4 networking;
  • IPv6 networking;
  • MAC80211 subsystem;
  • Multipath TCP;
  • Netfilter;
  • NET/ROM layer;
  • NFC subsystem;
  • Open vSwitch;
  • Rose network layer;
  • Network traffic control;
  • Network sockets;
  • Sun RPC protocol;
  • Integrity Measurement Architecture(IMA) framework;
  • Key management;
  • Simplified Mandatory Access Control Kernel framework;
  • FireWire sound drivers;
  • HD-audio driver;
  • Turtle Beach Wavefront ALSA driver;
  • STMicroelectronics SoC drivers;
  • USB sound devices;
  • KVM subsystem

Update instructions

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

Learn more about how to get the fixes.

ATTENTION: Due to an unavoidable ABI change the kernel updates have been given a new version number, which requires you to recompile and reinstall all third party kernel modules you might have installed. Unless you manually uninstalled the standard kernel metapackages (e.g. linux-generic, linux-generic-lts-RELEASE, linux-virtual, linux-powerpc), a standard system upgrade will automatically perform this as well.

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

Ubuntu Release Package Version
24.04 LTS noble linux-image-6.8.1-1047-realtime –  6.8.1-1047.48  
linux-image-intel-iot-realtime –  6.8.1-1047.48  
linux-image-realtime –  6.8.1-1047.48  
linux-image-realtime-6.8.1 –  6.8.1-1047.48  

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References

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