Integer overflow in Linux kernel - CVE-2026-98900

Vulnerability identifier: #VU157601

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-2026-98900

CWE-ID: CWE-190

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to potentially cause a denial of service through excessive kernel memory allocation and bypass grant-count limits.

The vulnerability exists due to insufficient grant-count validation and integer overflow in the Xen grant allocation function gntalloc_ioctl_alloc() when processing user-controlled grant allocation requests. A local user can supply excessive grant counts to trigger memory allocation before limit enforcement or cause arithmetic wraparound in grant accounting, potentially exhausting kernel memory or bypassing grant-count limits.

Linux kernel
Ubuntu
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-igx (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-aws (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-nvidia-tegra (Ubuntu package) - update to 5.15.0-1070.72
linux-nvidia-tegra-igx (Ubuntu package) - update to 5.15.0-1059.59
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1070.72~20.04.1
linux (Ubuntu package) - update to 7.0.0-42.42
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
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/2299822f3f466b5dcad2377bf63986199f881a6b
• https://git.kernel.org/stable/c/231542f4e43cf9837cb520664545e85fbe666b7b
• https://git.kernel.org/stable/c/641de086a05f349de7fc548612432bc2fed721ca
• https://git.kernel.org/stable/c/71a0cf87e19fb35c4292ca88985e376e613c900a
• https://git.kernel.org/stable/c/720554c04acba80018ded069d3e0984bebaee891
• https://git.kernel.org/stable/c/84d5727cef8eb9c8a28210ad248f1c70b223b065
• https://git.kernel.org/stable/c/e2806390aa1c4d5b3f7a68f10a56ae12c71c00d8

• Integer overflow in Linux kernel xen driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more
• Ubuntu update for linux-nvidia-tegra, linux-nvidia-tegra-5.15, linux-nvidia-tegra-igx
• Ubuntu update for linux, linux-aws, linux-aws-5.15 and more