Use-after-free in Linux kernel - CVE-2026-98033
Published: September 28, 2026
Vulnerability identifier: #VU152433
CSH Severity: Low
CVSS v4: 0 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-98033
CWE-ID: CWE-416
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to trigger a use-after-free.
The vulnerability exists due to improper preservation of map identity in BPF verifier callback frame constructors when invoking timer callbacks on nested inner maps. A local user can pair a timer from a second inner map with a first inner map and free the first map to trigger a use-after-free.
Affected software
Linux kernel
How to mitigate CVE-2026-98033
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3