Improper Check for Unusual or Exceptional Conditions in Linux kernel - CVE-2026-80946

Vulnerability identifier: #VU149444

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-2026-80946

CWE-ID: CWE-754

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 improper handling of hardened usercopy restrictions in the FUSE io-uring transport when copying FUSE request headers between a request slab object and userspace. A local user can trigger request header copying to cause a denial of service.

Systems with CONFIG_HARDENED_USERCOPY enabled can panic when the invalid slab-object usercopy is detected.

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 (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/194d0fb0ea4720535ff3168c9d04c7632cec7071
• https://git.kernel.org/stable/c/a47a416ff68d706dc3327ab583f86b9ee757358b
• https://git.kernel.org/stable/c/fd10f40af314f07b6d6e028b1ca25c8b49903aab

• Improper Check for Unusual or Exceptional Conditions in Linux kernel fuse
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more