CVE-2026-43083: Linux Kernel

Critical severity, CVSS 9.1. EPSS: 0.6% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: net: ioam6: fix OOB and missing lock When trace->type.bit6 is set: if (trace->type.bit6) { ... queue = skb_get_tx_queue(dev, skb); qdisc = rcu_dereference(queue->qdisc); This code can lead to an out-of-bounds access of the dev->_tx[] array when is_input is true. In such a case, the packet is on the RX path and skb->queue_mapping contains the RX queue index of the ingress device. If the ingress device has more RX queues than the egress device (dev) has TX queues, skb_get_queue_mapping(skb) will exceed dev->num_tx_queues. Add a check to avoid this situation since skb_get_tx_queue() does not clamp the index. This issue has also revealed that per queue visibility cannot be accurate and will be replaced later as a new feature. While at it, add missing lock around qdisc_qstats_qlen_backlog(). The function __ioam6_fill_trace_data() is called from both softirq and process contexts, hence the use of spin_lock_bh() here.

Affected products

• Linux Linux Kernel: from 5.17, before 6.18.24 (fixed in 6.18.24); from 6.19, before 6.19.14 (fixed in 6.19.14); version 7.0 only

Published 2026-05-06. Last modified 2026-06-17.