Improper handling of exceptional conditions in Linux kernel - CVE-2026-64290

Vulnerability identifier: #VU139702

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-2026-64290

CWE-ID: CWE-755

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 exception handling in iommufd_fault_fops_read() when handling a copy_to_user() failure while reading fault events. A local user can trigger a failing read operation to cause a denial of service.

The issue can lead to an infinite retry loop that spins the reader at 100% CPU while holding fault->mutex.

Linux kernel
Debian Linux
Ubuntu
linux (Debian package)
linux (Ubuntu package)
linux-gcp-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 (Debian package) - update to 6.12.101-1
linux (Ubuntu package) - addressed in versions 7.0.0-31.31, 7.0.0-31.31.1, 7.0.0-31.31~24.04.1, 7.0.0-1006.7, 7.0.0-1011.11~24.04.1, 7.0.0-1012.12, 7.0.0-1012.12~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1013.13

• https://git.kernel.org/stable/c/172fc8b19825a0f5884c38f2289188284e2d45ee
• https://git.kernel.org/stable/c/5539da127d03c1f6c2e2a49fdfbe331a0ccbdea8
• https://git.kernel.org/stable/c/f66c16b175509642ee7082df57c9bf3deaebae1a

• Improper handling of exceptional conditions in Linux kernel iommu iommufd driver
• Debian update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux
• Ubuntu update for linux-gcp-7.0