Integer overflow in Linux kernel - CVE-2026-90109

Vulnerability identifier: #VU151380

CSH Severity: Low

CVSS v4: 5.6 [CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-90109

CWE-ID: CWE-190

Exploitation vector: Local access

Exploit availability: No public exploit available

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

The vulnerability exists due to a 32-bit integer overflow in the gred_enqueue(), bfifo_enqueue(), and plug_enqueue() queue admission functions when calculating queue admission with a backlog exceeding 4 GiB. A local privileged user can attach a qdisc with a queue limit near 4 GiB and enqueue more than 4 GiB of traffic to cause a denial of service.

Linux kernel
Debian Linux
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)
linux (Debian 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
linux (Debian package) - update to 6.12.111-1

• https://git.kernel.org/stable/c/3fb51b3960342bbee563543f8d33710fd0fb5a96
• https://git.kernel.org/stable/c/4c660ee8c809637909f4f7eb1017f7b9401c75c4
• https://git.kernel.org/stable/c/8b2d8c70b969bf84f9e248bfaf2a7135129f2eb6
• https://git.kernel.org/stable/c/d98b92f3d57976ae185238946ec5ea0be32195aa

• Integer overflow in Linux kernel sched
• Debian update for linux
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more