title: Use-after-free in Linux kernel's net/sched: sch_qfq component
description: A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation.
When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue().
We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.
problem types: CWE-416 Use After Free
affected:
{
vendor: Linux
product: Kernel
packageName: kernel
repo: https://git.kernel.org
versions:
status: affected, version: 3.8, lessThan: 6.6, versionType: custom
defaultStatus: unaffected
}
metrics:
format: CVSS
scenarios: GENERAL
cvssV3_1: [
version: 3.1
attackVector: LOCAL
attackComplexity: LOW
privilegesRequired: LOW
userInteraction: NONE
scope: UNCHANGED
confidentialityImpact: HIGH
integrityImpact: HIGH
availabilityImpact: HIGH
baseSeverity: HIGH
baseScore: 7.8
vectorString: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
]