A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation.

If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free.

We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f.
Advisories
Source ID Title
Debian DLA Debian DLA DLA-3623-1 linux-5.10 security update
Debian DLA Debian DLA DLA-3710-1 linux security update
EUVD EUVD EUVD-2023-54476 A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation. If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free. We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f.
Ubuntu USN Ubuntu USN USN-6415-1 Linux kernel (OEM) vulnerabilities
Ubuntu USN Ubuntu USN USN-6439-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6439-2 Linux kernel (AWS) vulnerabilities
Ubuntu USN Ubuntu USN USN-6440-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6440-2 Linux kernel (Azure) vulnerabilities
Ubuntu USN Ubuntu USN USN-6440-3 Linux kernel (HWE) vulnerabilities
Ubuntu USN Ubuntu USN USN-6441-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6441-2 Linux kernel (GCP) vulnerabilities
Ubuntu USN Ubuntu USN USN-6441-3 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6442-1 Linux kernel (BlueField) vulnerabilities
Ubuntu USN Ubuntu USN USN-6444-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6444-2 Linux kernel (StarFive) vulnerabilities
Ubuntu USN Ubuntu USN USN-6445-1 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-6445-2 Linux kernel (Intel IoTG) vulnerabilities
Ubuntu USN Ubuntu USN USN-6446-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6446-2 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6446-3 Linux kernel (Oracle) vulnerabilities
Ubuntu USN Ubuntu USN USN-6460-1 Linux kernel vulnerabilities
Ubuntu USN Ubuntu USN USN-6466-1 Linux kernel (NVIDIA) vulnerabilities
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 04 Mar 2025 03:45:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Thu, 13 Feb 2025 17:30:00 +0000

Type Values Removed Values Added
Description A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation. If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free. We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f. A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation. If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free. We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f.

cve-icon MITRE

Status: PUBLISHED

Assigner: Google

Published:

Updated: 2025-02-27T21:00:32.991Z

Reserved: 2023-08-30T11:58:12.267Z

Link: CVE-2023-4623

cve-icon Vulnrichment

Updated: 2024-08-02T07:31:06.625Z

cve-icon NVD

Status : Analyzed

Published: 2023-09-06T14:15:12.357

Modified: 2025-03-20T16:59:51.550

Link: CVE-2023-4623

cve-icon Redhat

Severity : Important

Publid Date: 2023-09-06T00:00:00Z

Links: CVE-2023-4623 - Bugzilla

cve-icon OpenCVE Enrichment

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