Integer overflow in Linux kernel - CVE-2026-98547

Vulnerability identifier: #VU156849

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-2026-98547

CWE-ID: CWE-190

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service by exhausting CPU resources.

The vulnerability exists due to integer overflow in the Linux kernel's prb_calc_retire_blk_tmo() function when calculating the block retirement timeout for TPACKET_V3 packet rings. A local user can use CAP_NET_RAW privileges to configure a packet ring with a specially crafted block size, causing a negative timeout that makes the retirement timer repeatedly fire at the maximum rate and consume CPU resources.

The demonstrated trigger requires a 1 Gbps NIC; QEMU e1000 is a working example.

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/02afd75649a4e001031ed82153a5c39312ec0737
• https://git.kernel.org/stable/c/218a944b9e035d4b47d59c69af6ca13319da15fb
• https://git.kernel.org/stable/c/297acc571d5813db76b147c745b91031d5f9c960
• https://git.kernel.org/stable/c/56d82862a0a243ac14ba11b6d7b57ddc2d064b95
• https://git.kernel.org/stable/c/6279211e7d2456ecd195d236c9ee5e5c6fa5a17a
• https://git.kernel.org/stable/c/b2bcc6a254d6f27823a56787668ae4ee8cdb6e71
• https://git.kernel.org/stable/c/be1aacff399d519cc48d6b34354a54dd79041140
• https://git.kernel.org/stable/c/eb5b3838b9200dac04bfe33483db0ee8287456fb

• Integer overflow in Linux kernel packet
• 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