Improper Validation of Specified Quantity in Input in Linux kernel - CVE-2026-64149

Vulnerability identifier: #VU138492

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-2026-64149

CWE-ID: CWE-1284

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 resource validation in dma_map_resource() and dma-debug handling when mapping MMIO resources that share a sparse memory section with RAM. A local user can trigger the vulnerable code path to cause a denial of service.

This can occur on ARM64 systems with SPARSEMEM where MMIO addresses have struct pages in the same section as RAM, leading to a warning and DMA_MAPPING_ERROR during device probe.

Linux kernel
Ubuntu
linux-ibm (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

• https://git.kernel.org/stable/c/004a777879ff629f6e0ca3d09ad09fa3452bcc4d
• https://git.kernel.org/stable/c/181e67bc11c5ec5b87c6c512c2078752b23ca8d4
• https://git.kernel.org/stable/c/af0c3f05866237f7592219bfe05387bc3bfc99b5

• Improper Validation of Specified Quantity in Input in Linux kernel dma
• Ubuntu update for linux-ibm
• Ubuntu update for linux-azure
• Ubuntu update for linux-aws
• Ubuntu update for linux-nvidia-bos
• Ubuntu update for linux-nvidia