Use of Uninitialized Variable in Linux kernel - CVE-2026-63965

Vulnerability identifier: #VU138685

CSH Severity: Low

CVSS v4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-63965

CWE-ID: CWE-457

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to disclose sensitive information.

The vulnerability exists due to an uninitialized stack-based buffer in bmp580_trigger_handler() when processing sensor scan data for userspace. A local user can read exposed scan data to disclose sensitive information.

Two bytes of stack memory may be exposed to userspace per scan because 24-bit sensor data is copied into 32-bit fields, leaving the high byte of temperature and pressure values uninitialized.

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/387c86b582e0782ab332e7bfcd4e6e3f93922961
• https://git.kernel.org/stable/c/58dfb6fe9dc80270cf7cc014837af4cbf928e3aa
• https://git.kernel.org/stable/c/a58400f58f82f3d8de9c067aa7cda690228c1ecc

• Use of Uninitialized Variable in Linux kernel iio pressure driver
• 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