Improper update of reference count in Linux kernel - CVE-2026-98462

Vulnerability identifier: #VU156760

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-2026-98462

CWE-ID: CWE-911

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to potentially cause a denial of service through premature release of Bluetooth connection objects.

The vulnerability exists due to improper reference counting in the Linux kernel Bluetooth hci_bind_cis() and hci_connect_cis() functions when reusing connected isochronous stream (CIS) connections or handling configuration failures. A local user can trigger affected connection-handling paths to cause connection holds to be dropped without a corresponding acquisition, potentially leading to premature object release and a kernel crash.

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/072bc8659f22566083f8eef7dc5903bbcaf7804a
• https://git.kernel.org/stable/c/10f959cb435217b4b407864e5be0eb779e389490
• https://git.kernel.org/stable/c/3ff5a8d949e3a2a435d0a5ee05074cd371b0158a
• https://git.kernel.org/stable/c/947eb2f41f70d371eb16897ee4e8e32bff73b476
• https://git.kernel.org/stable/c/e06d549fcd4a0ba381ed67ddf1ab3c7a6ca4314c

• Improper update of reference count in Linux kernel bluetooth
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more