DEBIAN-CVE-2023-4921

Advisory lineage Upstream: 1 Downstream: 2
Upstream
CVE-2023-4921
Published: 12 Sept 2023, 20:15
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

12 Sept 2023, 20:15
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_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.

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 | < 6.5.6-1 | < 6.5.6-1

References (1)