Improper update of reference count in Linux kernel - CVE-2026-98498

Vulnerability identifier: #VU156799

CSH Severity: Low

CVSS v4: 2 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-98498

CWE-ID: CWE-911

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause resource retention that may lead to a denial of service.

The vulnerability exists due to a missing reference count decrement in mlx5_tc_ct_shared_counter_get() in the Linux kernel mlx5 driver when a reverse entry is found but its counter is already being released. A local user can trigger shared counter lookups under this condition to leave reverse entries permanently referenced, potentially exhausting resources and causing a denial of service.

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/0bf6bb567f0edaa771e7dd208ef98da50e6a4485
• https://git.kernel.org/stable/c/1f13989a0704bd98cab09f9bee63e2c8a98ad4dd
• https://git.kernel.org/stable/c/288721013605b4e0304e10f6a087b77f71cfad11
• https://git.kernel.org/stable/c/598daa5f95883f881a54967da40ce0fdfc1fdaa8
• https://git.kernel.org/stable/c/60eab87d0a798070bf5a856b1d9e5785ce92da53
• https://git.kernel.org/stable/c/79a3257280a335bbebbcd10d3895e8468bdcd6ae
• https://git.kernel.org/stable/c/99d8dc51663747078c031acac32edc6d90c8f1f7
• https://git.kernel.org/stable/c/c45c997d0c27359b502587897f775c5a277f0bd4

• Improper update of reference count in Linux kernel core en driver
• 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