Improper input validation in Linux kernel - CVE-2026-90051

Vulnerability identifier: #VU151431

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-2026-90051

CWE-ID: CWE-20

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to trigger TCP transmission failures.

The vulnerability exists due to improper input validation in tcp_sendmsg_locked() when sending devmem TCP data without a valid zero-copy binding. A local user can submit a devmem TCP transmission that lacks a valid zero-copy binding to trigger TCP transmission failures.

The issue occurs when the network interface does not support scatter-gather I/O.

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/125755776bc6d4dd53eaf551c87e3d460625d638
• https://git.kernel.org/stable/c/2151b2bcf6fcec52665f606eed20da068447f0b7
• https://git.kernel.org/stable/c/b04326c7927af7048fd4e730f5770cca350d0a60

• Improper input validation in Linux kernel ipv4
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more