NULL pointer dereference in Linux kernel - CVE-2026-74477

Vulnerability identifier: #VU143304

CSH Severity: Low

CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-74477

CWE-ID: CWE-476

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a NULL pointer dereference in hprobe_expire() in the uprobes subsystem when forking a task with a pending uretprobe. A local user can fork a traced task in this state to cause a denial of service.

The issue occurs in the clone() path due to a race condition where the associated uprobe may already be gone.

Linux kernel
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)

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

• https://git.kernel.org/stable/c/06c275a6c0a953ef1d763d11a6891fcc69ae2ac0
• https://git.kernel.org/stable/c/3bd35a5e272a1b7a3fb43acad9bdc599281b13fa
• https://git.kernel.org/stable/c/cc679d7a6303e84d769f2afcde1fc51c51f127cd

• NULL pointer dereference in Linux kernel events
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more