DEBIAN-CVE-2023-4623
Advisory lineage Upstream: 1 Downstream: 2
Upstream
Downstream
Published: 06 Sept 2023, 14:15
Last modified:28 Apr 2026, 20:26
Vulnerability Summary
Overall Risk (default)
medium
31/100 CVSS Score
7.8 HIGH
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected
Timeline
06 Sept 2023, 14:15
Published
Vulnerability first disclosed
28 Apr 2026, 20:26
Last Modified
Vulnerability information updated
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.
CVSS Metrics
- v3.1•HIGH•Score: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected Systems
- debian•linux
< 5.10.197-1 | < 6.1.55-1 | < 6.5.3-1 | < 6.5.3-1