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CVE-2026-43083

Linux Kernel out-of-bounds read

9.1 CRITICALEPSS 0.63%
  1. Published6 May 2026

Description

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.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Affected products

Linux Kernel≥ 5.17 < 6.18.24 · ≥ 6.19 < 6.19.14 · 7.0

Frequently asked

Is CVE-2026-43083 being actively exploited?

CVE-2026-43083 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.63%.

How severe is CVE-2026-43083?

CVE-2026-43083 has a CVSS 3.1 base score of 9.1, rated critical. EPSS estimates a 0.63% probability of exploitation.

Which products are affected by CVE-2026-43083?

Affected products include Linux Kernel.

How do I fix CVE-2026-43083?

Upgrade affected software to a fixed version, for example Linux Kernel 6.18.24 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-43083 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.