CVE-2026-43009

CVSS v3.1

7.8

High

Vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the Linux kernel eBPF verifier where the backtrack insn function fails to correctly handle atomic fetch operations. When encountering a BPF STX instruction with BPF ATOMIC and BPF FETCH, the logic treats the source register as a regular input rather than recognizing it also acts as a destination for the old memory value. This prevents the propagation of precision to the stack location, causing the verifier's path pruning to incorrectly treat two different states as equivalent. This flaw can be exploited by privileged users to bypass security restrictions, including within Windows Subsystem for Linux (WSL).

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Found an issue in the description? Have something to add? Feel free to write us 👾

dbugs@ptsecurity.com

Related Identifiers

CVE-2026-43009

Affected Products

Linux

Linux-Allwinner-5.19

Linux-Aws

Linux-Aws-5.0

Linux-Aws-5.11

Linux-Aws-5.13

Linux-Aws-5.15

Linux-Aws-5.19

Linux-Aws-5.3

Linux-Aws-5.8

Linux-Aws-6.14

Linux-Aws-6.17

Linux-Aws-6.2

Linux-Aws-6.5

Linux-Aws-6.8

Linux-Aws-Fips

Linux-Azure

Linux-Azure-5.11

Linux-Azure-5.13

Linux-Azure-5.15

Linux-Azure-5.19

Linux-Azure-5.3

Linux-Azure-5.8

Linux-Azure-6.11

Linux-Azure-6.14

Linux-Azure-6.17

Linux-Azure-6.2

Linux-Azure-6.5

Linux-Azure-6.8

Linux-Azure-Edge

Linux-Azure-Fde

Linux-Azure-Fde-5.15

Linux-Azure-Fde-5.19

Linux-Azure-Fde-6.14

Linux-Azure-Fde-6.17

Linux-Azure-Fde-6.2

Linux-Azure-Fde-6.8

Linux-Azure-Fips

Linux-Azure-Nvidia

Linux-Azure-Nvidia-6.14

Linux-Bluefield

Linux-Fips

Linux-Gcp

Linux-Gcp-5.11

Linux-Gcp-5.13

Linux-Gcp-5.15

Linux-Gcp-5.19

Linux-Gcp-5.3

Linux-Gcp-5.8

Linux-Gcp-6.11

Linux-Gcp-6.14

Linux-Gcp-6.17

Linux-Gcp-6.2

Linux-Gcp-6.5

Linux-Gcp-6.8

Linux-Gcp-Fips

Linux-Gke

Linux-Gke-4.15

Linux-Gkeop-5.15

Linux-Gke-5.4

Linux-Gkeop

Linux-Hwe

Linux-Hwe-5.11

Linux-Hwe-5.13

Linux-Hwe-5.15

Linux-Hwe-5.19

Linux-Hwe-5.8

Linux-Hwe-6.11

Linux-Hwe-6.14

Linux-Hwe-6.17

Linux-Hwe-6.2

Linux-Hwe-6.5

Linux-Hwe-6.8

Linux-Hwe-Edge

Linux-Ibm

Linux-Ibm-5.15

Linux-Ibm-6.8

Linux-Intel-5.13

Linux-Intel-Iot-Realtime

Linux-Intel-Iotg

Linux-Intel-Iotg-5.15

Linux-Kvm

Linux-Lowlatency

Linux-Lowlatency-Hwe-5.15

Linux-Lowlatency-Hwe-5.19

Linux-Lowlatency-Hwe-6.11

Linux-Lowlatency-Hwe-6.2

Linux-Lowlatency-Hwe-6.5

Linux-Lowlatency-Hwe-6.8

Linux-Lts

Linux-Nvidia

Linux-Nvidia-6.11

Linux-Nvidia-6.17

Linux-Nvidia-6.2

Linux-Nvidia-6.5

Linux-Nvidia-6.8

Linux-Nvidia-Lowlatency

Linux-Nvidia-Tegra

Linux-Nvidia-Tegra-5.15

Linux-Nvidia-Tegra-Igx

Linux-Oem

Linux-Oem-5.10

Linux-Oem-5.13

Linux-Oem-5.14

Linux-Oem-5.17

Linux-Oem-5.6

Linux-Oem-6.0

Linux-Oem-6.1

Linux-Oem-6.11

Linux-Oem-6.14

Linux-Oem-6.17

Linux-Oem-6.5

Linux-Oem-6.8

Linux-Oracle

Linux-Oracle-5.0

Linux-Oracle-5.11

Linux-Oracle-5.13

Linux-Oracle-5.15

Linux-Oracle-5.3

Linux-Oracle-5.8

Linux-Oracle-6.14

Linux-Oracle-6.17

Linux-Oracle-6.5

Linux-Oracle-6.8

Linux-Raspi

Linux-Raspi-Realtime

Linux-Raspi2

Linux-Realtime

Linux-Realtime-6.14

Linux-Realtime-6.17

Linux-Realtime-6.8

Linux-Riscv

Linux-Riscv-5.11

Linux-Riscv-5.15

Linux-Riscv-5.19

Linux-Riscv-5.8

Linux-Riscv-6.14

Linux-Riscv-6.17

Linux-Riscv-6.5

Linux-Riscv-6.8

Linux-Starfive-5.19

Linux-Starfive-6.2

Linux-Starfive-6.5

Linux-Xilinx

Linux-Xilinx-Zynqmp

Linux Kernel

CVE-2026-43009

Related Identifiers

Affected Products

References · 12