Use of Uninitialized Variable in Linux kernel - CVE-2026-46279

Vulnerability identifier: #VU134253

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-2026-46279

CWE-ID: CWE-457

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 uninitialized codetag references in page allocation tagging when freeing pages that were allocated before page_ext initialization. A local user can trigger kernel memory allocation and free activity to cause a denial of service.

This warning is only observed with CONFIG_MEM_ALLOC_PROFILING_DEBUG enabled and mem_profiling_compressed disabled.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-realtime (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (Ubuntu package)
linux-aws (Ubuntu package)
linux-raspi (Ubuntu package)
linux-azure (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-ibm (Ubuntu package)
linux-azure-fde (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux (Ubuntu package) - update to 7.0.0-27.27
linux-realtime (Ubuntu package) - update to 7.0.0-27.27.1
linux-gcp (Ubuntu package) - update to 7.0.0-1007.7
linux-oracle (Ubuntu package) - update to 7.0.0-1007.7
linux-aws (Ubuntu package) - update to 7.0.0-1008.8
linux-raspi (Ubuntu package) - update to 7.0.0-1014.14
linux-azure (Ubuntu package) - update to 7.0.0-1010.10
linux-nvidia (Ubuntu package) - update to 7.0.0-1013.13
linux-ibm (Ubuntu package) - update to 7.0.0-1009.9
linux-azure-fde (Ubuntu package) - update to 7.0.0-1009.9

• https://git.kernel.org/stable/c/6b1842775a460245e97d36d3a67d0cfba7c4ff79
• https://git.kernel.org/stable/c/b49dfabc38cad5e50af24f63edd124a10de3ebb6
• https://git.kernel.org/stable/c/d5b495ba9de0423ef39f8bd86729a885870c7efe

• Use of Uninitialized Variable in Linux kernel mm
• Ubuntu update for linux
• Ubuntu update for linux-raspi
• Ubuntu update for linux-nvidia
• Ubuntu update for linux-azure