Integer overflow in Linux kernel - CVE-2026-90109
Published: September 19, 2026
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
Vulnerability details
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.
Affected software
Linux kernel
How to mitigate CVE-2026-90109
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3