CVE-2026-52984: net/sched: netem: fix queue limit check to include reordered packets
In the Linux kernel, the following vulnerability has been resolved:
net/sched: netem: fix queue limit check to include reordered packets
The queue limit check in netemenqueue() uses q->tlen which only counts packets in the internal tfifo. Packets placed in sch->q by the reorder path (qdiscenqueuehead) are not counted, allowing the total queue occupancy to exceed sch->limit under reordering.
Include sch->q.qlen in the limit check.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.6.143.1-1 - Compensating control
Include sch->q.qlen in the queue limit check so netem_enqueue() accounts for both tfifo packets and the reorder/head enqueue path (__qdisc_enqueue_head), preventing total queue occupancy from exceeding sch->limit under reordering.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-52984?
The severity of CVE-2026-52984 is medium, with a CVSS score of 5.5.
How do I fix CVE-2026-52984?
To fix CVE-2026-52984, update the Linux kernel to the latest version that contains the patch.
What does CVE-2026-52984 affect?
CVE-2026-52984 affects the Linux kernel, specifically the netem module that manages network emulation.
What is the risk associated with CVE-2026-52984?
The risk associated with CVE-2026-52984 includes potential denial of service due to improper queue limit checks.
When was CVE-2026-52984 published?
CVE-2026-52984 was published on June 24, 2026.