Improper access control in Linux kernel - CVE-2026-74305

 

Improper access control in Linux kernel - CVE-2026-74305

Published: August 15, 2026


Vulnerability identifier: #VU142884
CSH Severity: Low
CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-74305
CWE-ID: CWE-284
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local user to bypass intended cgroup storage compatibility checks.

The vulnerability exists due to improper access control in bpf prog-array compatibility checks when validating tail-call chains involving cgroup local storage. A local user can load a storage-less BPF program that performs tail calls to bridge between programs with incompatible storage cookies to bypass intended cgroup storage compatibility checks.

Exploitation requires the ability to load and use BPF programs that participate in tail-call chains.


Affected software

Linux kernel
Ubuntu
openEuler
kernel-tools
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-source
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
python3-perf-debuginfo
kernel-extra-modules
linux (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-gcp (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-azure (Ubuntu package)

How to mitigate CVE-2026-74305

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
kernel-tools - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
bpftool - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
bpftool-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-debugsource - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-devel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-headers - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-source - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-tools-devel - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
perf - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
perf-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
python3-perf - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
python3-perf-debuginfo - addressed in versions 6.6.0-145.1.24.161, 6.6.0-145.3.29.160
kernel-extra-modules - update to 6.6.0-145.3.29.160
linux (Ubuntu package) - addressed in versions 5.15.0-195.205~20.04.1, 5.15.0-195.205, 5.15.0-198.208~20.04.1, 5.15.0-198.208+fips1, 5.15.0-1080.84, 5.15.0-1100.108, 5.15.0-1109.111, 5.15.0-1109.114, 5.15.0-1111.115~20.04.1, 5.15.0-1111.115, 5.15.0-1112.118~20.04.1, 5.15.0-1112.118, 5.15.0-1113.119, 5.15.0-1114.120, 5.15.0-1116.125~20.04.1, 5.15.0-1117.124~20.04.1, 5.15.0-1117.124, 5.15.0-1117.124+fips1, 5.15.0-1122.131~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1123.132, 5.15.0-1123.132+fips1, 5.15.0.195.160, 5.15.0.195.205~20.04.1, 5.15.0.198.114, 5.15.0.198.171, 5.15.0.198.208~20.04.1, 5.15.0.1080.83~20.04.1, 5.15.0.1100.99, 5.15.0.1109.105, 5.15.0.1109.113, 5.15.0.1111.108, 5.15.0.1111.115~20.04.1, 5.15.0.1112.111, 5.15.0.1112.118~20.04.1, 5.15.0.1113.112, 5.15.0.1114.110, 5.15.0.1116.120, 5.15.0.1117.113, 5.15.0.1117.120, 5.15.0.1117.124~20.04.1, 5.15.0.1122.131~20.04.1, 5.15.0.1123.107, 5.15.0.1123.121, 5.15.0.1123.132~20.04.1, 7.0.0-38.38, 7.0.0-38.38.1, 7.0.0-1008.9, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14, 7.0.0-1015.15
linux-nvidia (Ubuntu package) - addressed in versions 5.15.0-1112.113, 5.15.0.1112.112
linux-oracle-5.15 (Ubuntu package) - addressed in versions 5.15.0-1114.120~20.04.1, 5.15.0.1114.120~20.04.1
linux-gcp-5.15 (Ubuntu package) - addressed in versions 5.15.0-1118.128~20.04.1, 5.15.0.1118.128~20.04.1
linux-gcp (Ubuntu package) - addressed in versions 5.15.0-1118.128, 5.15.0-1118.128+fips1, 5.15.0.1118.107, 5.15.0.1118.115
linux-azure-fde (Ubuntu package) - addressed in versions 5.15.0-1122.131, 5.15.0.1122.131
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1035.38
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1015.15
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1017.17

External References

Related Security Bulletins