Infinite loop in Linux kernel - CVE-2026-63982

Vulnerability identifier: #VU138666

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-2026-63982

CWE-ID: CWE-835

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to improper loop detection in act_mirred in the traffic control subsystem when processing mirred redirect actions to ingress. A local user can configure redirect rules that create a mirred loop to cause a denial of service.

The issue occurs because loop state can be lost when packets are deferred into the backlog during ingress redirection.

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/45ac526a0d5733c3695946bd84ec57f24d8f5e66
• https://git.kernel.org/stable/c/66f4607fe788fc7d81bce0e2f7b3726ed2f71284
• https://git.kernel.org/stable/c/db875221ab08d213a83bf30196ae8b64d55a3403

• Infinite loop in Linux kernel sched
• 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