title: Use-after-free in Linux kernel's Performance Events subsystem
description: A use-after-free vulnerability in the Linux Kernel Performance Events system can be exploited to achieve local privilege escalation.
The perf_group_detach function did not check the event's siblings' attach_state before calling add_event_to_groups(), but remove_on_exec made it possible to call list_del_event() on before detaching from their group, making it possible to use a dangling pointer causing a use-after-free vulnerability.
We recommend upgrading past commit fd0815f632c24878e325821943edccc7fde947a2.
problem types: CWE-416 Use After Free
affected:
{
defaultStatus: unaffected
packageName: kernel
product: Linux Kernel
repo: https://git.kernel.org
vendor: Linux
versions:
lessThan: 6.3, status: affected, version: 5.13, versionType: custom
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: LOCAL
availabilityImpact: HIGH
baseScore: 7.8
baseSeverity: HIGH
confidentialityImpact: HIGH
integrityImpact: HIGH
privilegesRequired: LOW
scope: UNCHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
version: 3.1
]
format: CVSS
scenarios: GENERAL