Missing Release of Resource after Effective Lifetime in Linux kernel - CVE-2026-98451

Vulnerability identifier: #VU156749

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98451

CWE-ID: CWE-772

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to exhaust kernel resources and potentially cause a denial of service.

The vulnerability exists due to missing release of dentry references in the Linux kernel SMB client's cifs_atomic_open() function when opening an existing symbolic link with O_CREAT. A local user can repeatedly perform these opens on a CIFS filesystem to accumulate unreleased references and potentially 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/045532f920d86dd76600b635f9756e5fd671ddfc
• https://git.kernel.org/stable/c/3c07deb26273155c180aedfd9041ab58015d2521
• https://git.kernel.org/stable/c/70a7918fda54a06d836acc91eb9a3c7e860fe0a0
• https://git.kernel.org/stable/c/e66cf1625ec4a3fe68346119f371def713fd0a4d
• https://git.kernel.org/stable/c/ed03d547598c92a036f20e89156540995cac889a

• Missing Release of Resource after Effective Lifetime in Linux kernel smb client
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more