Ubuntu USN · USN-8617-1

Linux kernel (KVM) vulnerabilities

Published: Tue, 28 Jul 2026 06:46

CVE-2026-31418CVE-2026-31637CVE-2026-31685CVE-2026-31659CVE-2026-31682CVE-2026-43117CVE-2026-43383CVE-2026-23455CVE-2026-43038CVE-2026-43407CVE-2026-43414CVE-2026-31607CVE-2026-46043CVE-2026-46243CVE-2026-43011CVE-2026-43503CVE-2026-23272CVE-2026-31649

Summary

Several security issues were fixed in the Linux kernel.

Details

It was discovered that a logic flaw existed in the XFRM ESP-in-TCP subsystem in the Linux kernel when handling socket buffer fragments. This flaw is known as Fragnesia. A local attacker could use this to escalate privileges, or possibly escape a container. (CVE-2026-43503) 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: - InfiniBand drivers; - STMicroelectronics network drivers; - SCSI subsystem; - USB over IP driver; - SMB network file system; - Tracing infrastructure; - B.A.T.M.A.N. meshing protocol; - Ethernet bridge; - Ceph Core library; - IPv4 networking; - IPv6 networking; - Netfilter; - RxRPC session sockets; - X.25 network layer; (CVE-2026-23272, CVE-2026-23455, CVE-2026-31418, CVE-2026-31607, CVE-2026-31637, CVE-2026-31649, CVE-2026-31659, CVE-2026-31682, CVE-2026-31685, CVE-2026-43011, CVE-2026-43038, CVE-2026-43117, CVE-2026-43383, CVE-2026-43407, CVE-2026-43414, CVE-2026-46043, CVE-2026-46243)

Recommended actions per Ubuntu release

StackPatch playbook auto-generated per release codename and per affected package.

Ubuntu focal

linux-kvm→5.4.0-1148.157apt_upgrade
Standard apt upgrade. Install 5.4.0-1148.157 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-kvm
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-buildinfo-5.4.0-1148-kvm→5.4.0-1148.157apt_upgrade
Standard apt upgrade. Install 5.4.0-1148.157 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-buildinfo-5.4.0-1148-kvm
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-headers-5.4.0-1148-kvm→5.4.0-1148.157kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-headers-5.4.0-1148-kvm
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-headers-kvm→5.4.0.1148.144kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-headers-kvm
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-headers-kvm-5.4→5.4.0.1148.144kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-headers-kvm-5.4
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-image-5.4.0-1148-kvm→5.4.0-1148.157kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-image-5.4.0-1148-kvm
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-image-kvm→5.4.0.1148.144kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-image-kvm
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-image-kvm-5.4→5.4.0.1148.144kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-image-kvm-5.4
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-image-unsigned-5.4.0-1148-kvm→5.4.0-1148.157kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-image-unsigned-5.4.0-1148-kvm
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-kvm→5.4.0.1148.144apt_upgrade
Standard apt upgrade. Install 5.4.0.1148.144 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-kvm
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-kvm-5.4→5.4.0.1148.144apt_upgrade
Standard apt upgrade. Install 5.4.0.1148.144 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-kvm-5.4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-kvm-headers-5.4.0-1148→5.4.0-1148.157apt_upgrade
Standard apt upgrade. Install 5.4.0-1148.157 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-kvm-headers-5.4.0-1148
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-kvm-tools-5.4.0-1148→5.4.0-1148.157apt_upgrade
Standard apt upgrade. Install 5.4.0-1148.157 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-kvm-tools-5.4.0-1148
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-modules-5.4.0-1148-kvm→5.4.0-1148.157kernel_reboot
Kernel package — apt-upgrade then REBOOT to load the patched kernel.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-modules-5.4.0-1148-kvm
sudo reboot
```
Reboot is required. ~30-60s downtime; containers self-restart.
linux-tools-5.4.0-1148-kvm→5.4.0-1148.157apt_upgrade
Standard apt upgrade. Install 5.4.0-1148.157 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-tools-5.4.0-1148-kvm
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-tools-kvm→5.4.0.1148.144apt_upgrade
Standard apt upgrade. Install 5.4.0.1148.144 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-tools-kvm
```
Most apt upgrades restart their service automatically. needrestart lists anything else.
linux-tools-kvm-5.4→5.4.0.1148.144apt_upgrade
Standard apt upgrade. Install 5.4.0.1148.144 from the apt repo.
```
sudo apt-get update
sudo apt-get install --only-upgrade -y linux-tools-kvm-5.4
```
Most apt upgrades restart their service automatically. needrestart lists anything else.

Are YOU affected by USN-8617-1?

5-second check on your actual server. Reads /etc/os-release, uname -r, and dpkg-query; matches against the live USN + Debian Security Tracker feeds; tells you whether USN-8617-1 (and any other live CVE) applies. Anonymous, no signup.

curl https://mindsparkstack.com/scan.sh | bash

Form-based quickscan Read the bash source first

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