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.
CVE-2023-4921 - High Severity Vulnerability
Vulnerable Libraries - linuxv4.19, linuxv4.19
Vulnerability Details
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.
Publish Date: 2023-09-12
URL: CVE-2023-4921
CVSS 3 Score Details (7.8)
Base Score Metrics: - Exploitability Metrics: - Attack Vector: Local - Attack Complexity: Low - Privileges Required: Low - User Interaction: None - Scope: Unchanged - Impact Metrics: - Confidentiality Impact: High - Integrity Impact: High - Availability Impact: High
For more information on CVSS3 Scores, click here.Suggested Fix
Type: Upgrade version
Origin: https://www.linuxkernelcves.com/cves/CVE-2023-4921
Release Date: 2023-09-12
Fix Resolution: v4.14.326,v4.19.295,v5.4.257,v5.10.195,v5.15.132,v6.1.54,v6.6-rc1
Step up your Open Source Security Game with Mend here