Missing Release of File Descriptor or Handle after Effective Lifetime in Linux kernel - CVE-2026-98453

Vulnerability identifier: #VU156751

CSH Severity: Medium

CVSS v4: 6.9 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98453

CWE-ID: CWE-775

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause resource leakage that may lead to a denial of service.

The vulnerability exists due to missing release of a remote handle in the Linux kernel SMB client's SMB2_open() function when parsing malformed create contexts in a successful CREATE response. A remote attacker can return a specially crafted response from an SMB server to leave a server-side handle open and the num_remote_opens count elevated, potentially causing resource exhaustion through repeated failures.

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/566820af017e81497fb5e9d3ad6e7ffe2828bc8b
• https://git.kernel.org/stable/c/80c67cc71d32ccafc89a29b669243b40d81b930f
• https://git.kernel.org/stable/c/cdb36b09fb1f86d638d0afb44d621ed3f7c1d8eb
• https://git.kernel.org/stable/c/eaa97a196a107d4ef8775df2248181624151812e
• https://git.kernel.org/stable/c/f09875ff901e933e7b22c913daf51d21e9d93a45

• Missing Release of File Descriptor or Handle 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