Uncontrolled Recursion in Linux kernel - CVE-2026-98613

Vulnerability identifier: #VU156920

CSH Severity: Low

CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98613

CWE-ID: CWE-674

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local privileged user to exhaust the kernel stack and cause a denial of service.

The vulnerability exists due to uncontrolled recursion caused by missing ownership-depth validation in the Linux kernel BPF subsystem when handling object ownership through local referenced kernel pointers. A local privileged user can construct deeply nested object ownership chains and trigger destruction of the head object to exhaust the kernel stack and cause a denial of service.

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/4105870a4b8afe852aeb24a6dd58e1836cc4ce58
• https://git.kernel.org/stable/c/92aa0502c781d72bb9685245c3280efb3766a110
• https://git.kernel.org/stable/c/9c11e543fec32e92b3aa3f693339ca3ee79ea9dd
• https://git.kernel.org/stable/c/bfc888f04588f591851e95c974954cfca58e6c19

• Uncontrolled Recursion in Linux kernel bpf prog_tests
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more