Always-Incorrect Control Flow Implementation in Linux kernel - CVE-2026-63975

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Main Vulnerability Database Vulnerabilities #VU138677

Always-Incorrect Control Flow Implementation in Linux kernel - CVE-2026-63975

Published: July 20, 2026


Vulnerability identifier: #VU138677
CSH Severity: Medium
CVSS v4: 7.1 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-63975
CWE-ID: CWE-670
Exploitation vector: Adjecent network
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper handling of channel deletion during list iteration in l2cap_ecred_conn_rsp in the Bluetooth L2CAP subsystem when processing a crafted L2CAP credit-based connection response with an already-assigned destination CID. A remote attacker can send a specially crafted Bluetooth packet to cause a denial of service.

The issue occurs when a duplicate destination CID is received for an L2CAP extended credit based connection response.


Affected software

Linux kernel
openEuler
Ubuntu
python3-perf-debuginfo
kernel
bpftool
bpftool-debuginfo
kernel-debuginfo
kernel-debugsource
kernel-devel
kernel-headers
kernel-source
kernel-tools
kernel-tools-debuginfo
kernel-tools-devel
perf
perf-debuginfo
python3-perf
kernel-extra-modules
linux-ibm (Ubuntu package)
linux-aws (Ubuntu package)
linux-azure (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

How to mitigate CVE-2026-63975

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
python3-perf-debuginfo - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
bpftool - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
bpftool-debuginfo - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-debuginfo - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-debugsource - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-devel - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-headers - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-source - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-tools - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-tools-debuginfo - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-tools-devel - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
perf - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
perf-debuginfo - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
python3-perf - addressed in versions 5.10.0-327.0.0.228, 6.6.0-145.1.20.157, 6.6.0-145.3.29.160
kernel-extra-modules - update to 6.6.0-145.3.29.160
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
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

External References

Related Security Bulletins