1. Ubuntu Security Notices
  2. USN-8497-1

USN-8497-1: Linux kernel (Low Latency) vulnerabilities

Publication date

2 July 2026

Overview

Several security issues were fixed in the Linux kernel.

Releases

Packages

Details

It was discovered that the Linux kernel did not properly handle shared page
fragments during socket buffer operations, collectively known as Dirty
Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the
RxRPC networking subsystem when processing paged fragments. A local
attacker could use this to escalate privileges, or possibly escape a
container. (CVE-2026-43284, CVE-2026-43500, CVE-2026-45998, CVE-2026-46000)

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,

It was discovered that the Linux kernel did not properly handle shared page
fragments during socket buffer operations, collectively known as Dirty
Frag. A logic flaw existed in the XFRM ESP-in-TCP subsystem and in the
RxRPC networking subsystem when processing paged fragments. A local
attacker could use this to escalate privileges, or possibly escape a
container. (CVE-2026-43284, CVE-2026-43500, CVE-2026-45998, CVE-2026-46000)

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,
CVE-2026-46300)

Qualys discovered that a race condition existed in the ptrace subsystem of
the Linux kernel when privileged processes are exiting. An unprivileged
local attacker could use this issue to expose sensitive information.
(CVE-2026-46333)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0
contain a memory leak when handling AppArmor notifications. A local
attacker could use this to cause resource exhaustion. (CVE-2026-47326)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0
contain a NULL pointer dereference when handling AppArmor notifications. A
local attacker could use this to cause a kernel oops. (CVE-2026-47327)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0
contained an invalid free when handling AppArmor notifications. A local
attacker could use this to corrupt kernel memory. (CVE-2026-47328)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0
contained insufficient validation of AppArmor notification responses. A
local attacker could use this to allow crafted responses to be processed.
(CVE-2026-47329)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0 used
an uninitialized variable when handling AppArmor notifications. A local
attacker could use this to cause incorrect caching of data.
(CVE-2026-47330)

Tristan Madani discovered that Ubuntu Linux kernel 6.8 contained a use-
after-free (UAF) bug. A local attacker could use this to cause memory
corruption and, theoretically, arbitrary code execution. (CVE-2026-47331)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0
contained an out-of-bounds (OOB) read when handling AppArmor notifications.
A local attacker could use this to cause information disclosure of kernel
memory. (CVE-2026-47332)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0
contained a out-of-bounds (OOB) read when handling AppArmor notifications.
A local attacker could use this to cause kernel memory corruption and,
theoretically, influence processing of AppArmor policies. (CVE-2026-47333)

Tristan Madani discovered that Ubuntu Linux kernel 6.8, 6.17 and 7.0
contained incorrect holding of locks when handling AppArmor notifications.
A local attacker could use this to cause a kernel panic or deadlock.
(CVE-2026-47334)

Tristan Madani discovered that Ubuntu Linux kernel 6.8 contained a NULL
pointer dereference when handling AppArmor notifications. A local attacker
could use this to cause a kernel panic. (CVE-2026-47335)

Tristan Madani discovered that Ubuntu Linux kernel 6.8 used an
uninitialized variable when handling AppArmor AF_INET/AF_INET6 socket
mediation. A local attacker could use this to influence processing of fine-
grained network socket mediation. (CVE-2026-47336)

Tristan Madani and Trevor Lawrence have each independently discovered that
Ubuntu Linux kernel 6.8, 6.17 and 7.0 contained a NULL pointer dereference
when handling AppArmor network socket mediation. A local attacker could use
this to cause a kernel oops. (CVE-2026-47337)

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;
  • MIPS architecture;
  • PowerPC architecture;
  • x86 architecture;
  • Block layer subsystem;
  • Cryptographic API;
  • ACPI drivers;
  • ATM drivers;
  • RNBD block device driver;
  • Ublk userspace block driver;
  • Bus devices;
  • Character device driver;
  • TPM device driver;
  • Clock framework and drivers;
  • Clocksource drivers;
  • CPU idle management framework;
  • Hardware crypto device drivers;
  • DMA engine subsystem;
  • EFI core;
  • GPIO subsystem;
  • GPU drivers;
  • HID subsystem;
  • Hardware monitoring drivers;
  • IIO subsystem;
  • InfiniBand drivers;
  • IOMMU subsystem;
  • Multiple devices driver;
  • Media drivers;
  • Multifunction device drivers;
  • Broadcom VK accelerator driver;
  • MOST (Media Oriented Systems Transport) drivers;
  • MTD block device drivers;
  • Ethernet bonding driver;
  • Network drivers;
  • Mellanox network drivers;
  • STMicroelectronics network drivers;
  • NTB driver;
  • NVME drivers;
  • PCI subsystem;
  • Performance monitor drivers;
  • Pin controllers subsystem;
  • x86 platform drivers;
  • Power supply drivers;
  • RapidIO drivers;
  • RAS (Reliability, Availability, Serviceability) subsystem;
  • Remote Processor subsystem;
  • RPMSG subsystem;
  • S/390 drivers;
  • SCSI subsystem;
  • MediaTek SoC drivers;
  • Texas Instruments SoC drivers;
  • SPI subsystem;
  • Greybus lights staging drivers;
  • Realtek RTL8723BS SDIO drivers;
  • UFS subsystem;
  • ChipIdea USB driver;
  • DesignWare USB3 driver;
  • USB over IP driver;
  • vDPA drivers;
  • Virtio Host (VHOST) subsystem;
  • Framebuffer layer;
  • BTRFS file system;
  • File systems infrastructure;
  • Ceph distributed file system;
  • Ext4 file system;
  • F2FS file system;
  • FAT file system;
  • GFS2 file system;
  • HFS+ file system;
  • JFS file system;
  • Network file system (NFS) server daemon;
  • NILFS2 file system;
  • NTFS3 file system;
  • OCFS2 file system;
  • Proc file system;
  • Pstore file system;
  • Diskquota system;
  • SMB network file system;
  • XFS file system;
  • Audit subsystem;
  • Memory Management;
  • IPv6 networking;
  • Netfilter;
  • Tracing infrastructure;
  • Kernel kexec() syscall;
  • RCU subsystem;
  • Scheduler infrastructure;
  • Scatterlist API;
  • 9P file system network protocol;
  • Asynchronous Transfer Mode (ATM) subsystem;
  • B.A.T.M.A.N. meshing protocol;
  • Bluetooth subsystem;
  • Ethernet bridge;
  • Ceph Core library;
  • Networking core;
  • IPv4 networking;
  • KCM (Kernel Connection Multiplexor) sockets driver;
  • Multipath TCP;
  • NFC subsystem;
  • RDS protocol;
  • RxRPC session sockets;
  • Network traffic control;
  • SMC sockets;
  • Sun RPC protocol;
  • X.25 network layer;
  • XFRM subsystem;
  • AppArmor security module;
  • Simplified Mandatory Access Control Kernel framework;
  • SOF drivers;
  • USB sound devices

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-6.8.0-134-lowlatency –  6.8.0-134.134.1
linux-image-6.8.0-134-lowlatency-64k –  6.8.0-134.134.1
linux-image-lowlatency –  6.8.0-134.134.1
linux-image-lowlatency-6.8 –  6.8.0-134.134.1
linux-image-lowlatency-64k –  6.8.0-134.134.1
linux-image-lowlatency-64k-6.8 –  6.8.0-134.134.1
22.04 LTS jammy linux-image-6.8.0-134-lowlatency –  6.8.0-134.134.1~22.04.1
linux-image-6.8.0-134-lowlatency-64k –  6.8.0-134.134.1~22.04.1
linux-image-lowlatency-6.8 –  6.8.0-134.134.1~22.04.1
linux-image-lowlatency-64k-6.8 –  6.8.0-134.134.1~22.04.1
linux-image-lowlatency-64k-hwe-22.04 –  6.8.0-134.134.1~22.04.1
linux-image-lowlatency-hwe-22.04 –  6.8.0-134.134.1~22.04.1

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References

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