In the Linux kernel, the following vulnerability has been resolved:
net: sched: fix ordering of qlen adjustment
Changes to sch->q.qlen around qdisc_tree_reduce_backlog() need to happen before a call to said function because otherwise it may fail to notify parent qdiscs when the child is about to become empty.
Exploitability
AV:LAC:LPR:LUI:NScope
S:UImpact
C:NI:NA:H5.5/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H