Use of uninitialized resource in Linux kernel - CVE-2026-90300

Vulnerability identifier: #VU151183

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-2026-90300

CWE-ID: CWE-908

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause nondeterministic BPF map-key behavior.

The vulnerability exists due to use of uninitialized memory in __bpf_get_task_stack when a BPF stack helper encounters an error. A local user can invoke an affected BPF stack helper to cause nondeterministic BPF map-key behavior.

The condition occurs when the task stack cannot be acquired or task registers are unavailable.

Linux kernel
Debian Linux
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-ibm (Ubuntu package)
linux-hwe-7.0 (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux (Debian package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-ibm (Ubuntu package) - update to 7.0.0-1017.17
linux-hwe-7.0 (Ubuntu package) - update to 7.0.0-42.42~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1017.17
linux (Debian package) - update to 6.12.115-2

• https://git.kernel.org/stable/c/f523359c4789bb0396d2d642464a6e2fd4f2299d
• https://git.kernel.org/stable/c/f5d242825ca417bb6afe35fde6e8880f97ca43fb

• Use of uninitialized resource in Linux kernel bpf
• Debian update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more