Division by zero in Linux kernel - CVE-2026-98408

Vulnerability identifier: #VU155911

CSH Severity: Low

CVSS v4: 0 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98408

CWE-ID: CWE-369

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to division by zero in the rzv2h_wdt_probe() function of the RZ/V2H watchdog driver when initializing the watchdog with a zero clock rate. A local user can trigger the affected initialization path under this condition to 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/0dd78d9d9b546de08e2ae391541f48cea0a9b842
• https://git.kernel.org/stable/c/6274281c41efa8dd1aa5234c59ad904ff89d7af4
• https://git.kernel.org/stable/c/eb14ee406e1d0fbbfb857f0eaa710daa8c2dc30e

• Division by zero in Linux kernel watchdog driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more