Race condition in Linux kernel - CVE-2026-98907

Vulnerability identifier: #VU157608

CSH Severity: Low

CVSS v4: 1.8 [CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98907

CWE-ID: CWE-362

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local privileged user to potentially cause a denial of service by disrupting Btrfs superblock reads.

The vulnerability exists due to a race condition in the Btrfs sb_write_pointer() function when reading a superblock from the block device page cache concurrently with block size changes. A local privileged user can attempt to overlap block size changes through BLKBSZSET with reads through read_cache_page_gfp() to potentially cause inconsistent reads and disrupt filesystem operations.

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/123b9a545f4d0348e81f558a032bf2a93ee5722f
• https://git.kernel.org/stable/c/1a6c92aa7242a04e4349c0ea213dbf703a1c9891
• https://git.kernel.org/stable/c/80cd97c5e90096d040a623851795eac92fbd0ff1
• https://git.kernel.org/stable/c/a0dc28359a8a26f970ccd250b126a2e0bd4118a5
• https://git.kernel.org/stable/c/a58cab4535f085adc0f93d7efd7952ef437371da
• https://git.kernel.org/stable/c/c9b38f2eab5a9bd74087390318d93ccdd8d2deff

• Race condition in Linux kernel btrfs
• 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