Out-of-bounds read in Linux kernel - CVE-2026-98601

Vulnerability identifier: #VU156905

CSH Severity: Medium

CVSS v4: 5.1 [CVSS:4.0/AV:P/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98601

CWE-ID: CWE-125

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows an attacker with physical access to system to cause a denial of service by potentially crashing the kernel.

The vulnerability exists due to an out-of-bounds read in btintel_pcie_msix_rx_handle() when processing device-supplied RX completion descriptors in DMA-coherent memory. An attacker with physical access to system can supply an out-of-range frbd_tag through a controlled PCIe device to cause an invalid data-buffer pointer dereference and potentially crash the kernel.

Linux kernel
Ubuntu
linux (Ubuntu package)
linux-aws (Ubuntu package)
linux-gcp (Ubuntu package)
linux-oracle (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 (Ubuntu package) - update to 7.0.0-42.42
linux-aws (Ubuntu package) - update to 7.0.0-1016.17
linux-gcp (Ubuntu package) - update to 7.0.0-1016.18
linux-oracle (Ubuntu package) - update to 7.0.0-1015.16
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/37a11129345337efd6eef8e62b03b6348cd0dd8b
• https://git.kernel.org/stable/c/8ec5838a35b03ac0cf3602452a369898051ffaf9
• https://git.kernel.org/stable/c/b29b70bfa12133423924fcd0327c19a802f7e368
• https://git.kernel.org/stable/c/f42cd95e679d5b78611cd2208cd1c41ad0045ffa

• Out-of-bounds read in Linux kernel bluetooth driver
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more