Use-after-free in Linux kernel - CVE-2026-93099

Vulnerability identifier: #VU150905

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-2026-93099

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to trigger a use-after-free condition.

The vulnerability exists due to use-after-free in the resctrl monitoring worker delayed work embedded in rdt_l3_mon_domain when CPU hotplug removes a domain while a worker is blocked waiting for cpus_read_lock(). A local user can trigger CPU hotplug during monitoring work to trigger a use-after-free condition.

Linux kernel
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)

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

• https://git.kernel.org/stable/c/2566b5cd6a275c124e8f154fef6e815f92ec8d5c
• https://git.kernel.org/stable/c/b86dbfe4583bf134932a6cc45bf25b12c10a0b2f

• Use-after-free in Linux kernel resctrl
• Ubuntu update for linux-oem-7.0
• Ubuntu update for linux, linux-aws, linux-gcp and more