{"schema_version":"1.9.0","id":"CVE-2023-4921","published":"2023-09-12T19:45:19.367Z","modified":"2026-08-12T03:51:31.895723305Z","related":["ALSA-2024:0897","SUSE-SU-2023:4030-1","SUSE-SU-2023:4031-1","SUSE-SU-2023:4032-1","SUSE-SU-2023:4033-1","SUSE-SU-2023:4035-1","SUSE-SU-2023:4057-1","SUSE-SU-2023:4058-1","SUSE-SU-2023:4071-1","SUSE-SU-2023:4072-1","SUSE-SU-2023:4072-2","SUSE-SU-2023:4093-1","SUSE-SU-2023:4095-1","SUSE-SU-2023:4142-1","SUSE-SU-2023:4347-1","SUSE-SU-2024:0469-1","SUSE-SU-2024:0474-1","SUSE-SU-2024:0478-1","SUSE-SU-2024:0514-1","SUSE-SU-2024:0515-1","SUSE-SU-2024:0516-1","SUSE-SU-2024:0622-1","SUSE-SU-2024:0624-1","SUSE-SU-2024:0655-1","SUSE-SU-2024:0666-1","SUSE-SU-2024:0685-1","SUSE-SU-2024:0698-1","SUSE-SU-2024:0727-1","USN-6454-1","USN-6454-2","USN-6454-3","USN-6454-4"],"summary":"Use-after-free in Linux kernel's net/sched: sch_qfq component","details":"A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation.\n\nWhen 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().\n\nWe recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8.","affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git","events":[{"introduced":"19f949f52599ba7c3f67a5897ac6be14bfcb1200"},{"fixed":"ffc253263a1375a65fa6c9f62a893e9767fbebfa"}],"database_specific":{"extracted_events":[{"introduced":"3.8"},{"fixed":"6.6"}],"source":"AFFECTED_FIELD"}}],"versions":["v6.6-rc1","v6.6-rc5","v6.6-rc3","v6.6-rc7","v6.6-rc6","v6.6-rc4","v6.6-rc2","v6.5","v6.5-rc1","v6.5-rc2","v6.5-rc7","v6.5-rc4","v6.5-rc3","v6.5-rc6","v6.5-rc5","v6.4","v6.4-rc7","v6.4-rc1","v6.4-rc6","v6.4-rc5","v6.4-rc3","v6.4-rc4","v6.4-rc2","v6.3","v6.3-rc1","v6.3-rc7","v6.3-rc2","v6.3-rc3","v6.3-rc5","v6.3-rc6","v6.3-rc4","v6.2-rc6","v6.2-rc1","v6.2","v6.2-rc2","v6.2-rc8","v6.2-rc5","v6.2-rc4","v6.2-rc7","v6.2-rc3","v6.1-rc1","v6.1","v6.1-rc8","v6.1-rc3","v6.1-rc6","v6.1-rc7","v6.1-rc4","v6.1-rc2","v6.1-rc5","v6.0-rc1","v6.0","v6.0-rc7","v6.0-rc3","v6.0-rc2","v6.0-rc6","v6.0-rc4","v6.0-rc5","v5.19","v5.19-rc1","v5.19-rc5","v5.19-rc8","v5.19-rc6","v5.18","v5.19-rc2","v5.19-rc7","v5.19-rc3","v5.19-rc4","v5.18-rc1","v5.18-rc7","v5.18-rc2","v5.18-rc5","v5.17","v5.18-rc4","v5.18-rc3","v5.18-rc6","v5.17-rc6","v5.17-rc4","v5.17-rc8","v5.17-rc7","v5.17-rc1","v5.17-rc3","v5.17-rc2","v5.17-rc5","v5.16","v5.16-rc1","v5.16-rc8","v5.16-rc5","v5.16-rc6","v5.16-rc7","v5.16-rc3","v5.16-rc2","v5.16-rc4","v5.15","v5.15-rc2","v5.15-rc1","v5.15-rc4","v5.15-rc7","v5.15-rc3","v5.15-rc5","v5.15-rc6","v5.14","v5.14-rc3","v5.14-rc1","v5.14-rc2","v5.14-rc7","v5.14-rc6","v5.13-rc1","v5.14-rc5","v5.14-rc4","v5.13","v5.13-rc6","v5.13-rc7","v5.13-rc3","v5.13-rc2","v5.13-rc4","v5.13-rc5","v5.12","v5.12-rc2","v5.12-rc1-dontuse","v5.12-rc1","v5.12-rc8","v5.12-rc3","v5.12-rc7","v5.12-rc5","v5.12-rc6","v5.12-rc4","v5.10","v5.11","v5.11-rc3","v5.11-rc7","v5.11-rc6","v5.11-rc5","v5.11-rc1","v5.11-rc4","v5.11-rc2","v5.10-rc1","v5.10-rc7","v5.10-rc4","v5.10-rc3","v5.10-rc6","v5.9","v5.10-rc2","v5.10-rc5","v5.9-rc1","v5.9-rc7","v5.9-rc8","v5.9-rc6","v5.9-rc4","v5.9-rc5","v5.9-rc3","v5.9-rc2","v5.8","v5.7","v5.8-rc2","v5.8-rc1","v5.8-rc7","v5.8-rc5","v5.8-rc3","v5.8-rc4","v5.8-rc6","v5.7-rc4","v5.7-rc7","v5.7-rc1","v5.7-rc3","v5.7-rc2","v5.7-rc5","v5.7-rc6","v5.6","v5.6-rc1","v5.6-rc7","v5.6-rc6","v5.6-rc3","v5.6-rc4","v5.6-rc2","v5.6-rc5","v5.5","v5.5-rc5","v5.5-rc7","v5.5-rc2","v5.5-rc1","v5.4","v5.5-rc4","v5.5-rc3","v5.5-rc6","v5.4-rc1","v5.4-rc6","v5.4-rc3","v5.4-rc4","v5.4-rc8","v5.4-rc7","v5.4-rc5","v5.3","v5.4-rc2","v5.3-rc5","v5.3-rc1","v5.3-rc2","v5.3-rc3","v5.3-rc8","v5.3-rc7","v5.3-rc4","v5.2","v5.3-rc6","v5.2-rc2","v5.2-rc7","v5.2-rc4","v5.2-rc1","v5.2-rc5","v5.2-rc6","v5.2-rc3","v5.1","v5.0-rc8","v5.1-rc7","v5.1-rc1","v5.1-rc6","v5.1-rc5","v5.0","v5.1-rc3","v5.1-rc2","v5.1-rc4","v5.0-rc1","v5.0-rc4","v5.0-rc3","v5.0-rc6","v5.0-rc7","v5.0-rc2","v5.0-rc5","v4.20-rc1","v4.19","v4.20","v4.20-rc7","v4.20-rc5","v4.20-rc6","v4.20-rc4","v4.20-rc2","v4.20-rc3","v4.19-rc2","v4.19-rc8","v4.19-rc4","v4.19-rc1","v4.19-rc7","v4.19-rc6","v4.19-rc5","v4.19-rc3","v4.18","v4.18-rc1","v4.18-rc8","v4.18-rc2","v4.18-rc5","v4.18-rc6","v4.18-rc7","v4.17","v4.18-rc3","v4.18-rc4","v4.17-rc1","v4.17-rc2","v4.17-rc7","v4.17-rc3","v4.17-rc4","v4.16","v4.17-rc6","v4.17-rc5","v4.16-rc7","v4.16-rc4","v4.16-rc1","v4.16-rc2","v4.16-rc5","v4.16-rc3","v4.16-rc6","v4.14","v4.15","v4.15-rc1","v4.15-rc4","v4.15-rc9","v4.15-rc8","v4.15-rc7","v4.15-rc3","v4.15-rc2","v4.15-rc5","v4.15-rc6","v4.14-rc1","v4.14-rc7","v4.14-rc3","v4.13","v4.14-rc8","v4.14-rc4","v4.14-rc6","v4.14-rc2","v4.14-rc5","v4.13-rc2","v4.13-rc1","v4.13-rc3","v4.13-rc7","v4.13-rc4","v4.13-rc5","v4.13-rc6","v4.12-rc1","v4.12","v4.12-rc5","v4.12-rc7","v4.12-rc6","v4.12-rc4","v4.12-rc2","v4.12-rc3","v4.11","v4.11-rc1","v4.11-rc6","v4.11-rc8","v4.11-rc7","v4.11-rc3","v4.11-rc5","v4.11-rc2","v4.11-rc4","v4.10","v4.9","v4.10-rc8","v4.10-rc3","v4.10-rc1","v4.10-rc7","v4.10-rc6","v4.10-rc2","v4.10-rc5","v4.10-rc4","v4.9-rc7","v4.9-rc6","v4.9-rc8","v4.9-rc1","v4.9-rc5","v4.9-rc3","v4.9-rc4","v4.9-rc2","v4.8","v4.8-rc8","v4.8-rc2","v4.8-rc1","v4.8-rc7","v4.8-rc6","v4.8-rc5","v4.8-rc4","v4.8-rc3","v4.7","v4.7-rc4","v4.7-rc2","v4.7-rc1","v4.7-rc7","v4.7-rc6","v4.7-rc3","v4.7-rc5","v4.6","v4.6-rc1","v4.6-rc6","v4.6-rc4","v4.6-rc7","v4.6-rc5","v4.5-rc4","v4.6-rc2","v4.6-rc3","v4.5","v4.4","v4.5-rc1","v4.5-rc6","v4.5-rc2","v4.5-rc7","v4.5-rc5","v4.5-rc3","v4.4-rc1","v4.4-rc2","v4.4-rc8","v4.4-rc3","v4.4-rc7","v4.4-rc5","v4.4-rc6","v4.4-rc4","v4.3","v4.3-rc1","v4.3-rc6","v4.3-rc4","v4.3-rc2","v4.3-rc7","v4.3-rc5","v4.3-rc3","v4.2","v4.2-rc2","v4.2-rc1","v4.2-rc8","v4.2-rc4","v4.2-rc6","v4.2-rc7","v4.0-rc5","v4.2-rc5","v4.2-rc3","v4.1-rc2","v4.1","v4.1-rc1","v4.1-rc8","v4.1-rc7","v4.1-rc6","v4.1-rc3","v4.1-rc4","v4.0","v4.1-rc5","v4.0-rc1","v4.0-rc2","v4.0-rc7","v4.0-rc3","v4.0-rc6","v4.0-rc4","v3.19","v3.19-rc7","v3.19-rc5","v3.19-rc1","v3.19-rc6","v3.19-rc4","v3.18-rc1","v3.19-rc3","v3.19-rc2","v3.18","v3.18-rc7","v3.18-rc6",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