CVE-2026-43083
CriticalIn 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 score
9.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Weakness type
CWE-125CVE-2026-43083 is a Out-of-bounds Read vulnerability
What is Out-of-bounds Read?
The product reads data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE
Affected versions
Linux kernel versions
5.17
and later are affected. Fixed in
6.18.24,
6.19.14,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-43083 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/6d1d9ed9b409e0662241e3d245d574a18f643494
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PatchKernel patch commithttps://git.kernel.org/stable/c/95a1334748c95dd15546056280ade0c4b8dd7b78
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PatchKernel patch commithttps://git.kernel.org/stable/c/b30b1675aa2bcf0491fd3830b051df4e08a7c8ca
Frequently asked questions
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What is CVE-2026-43083?
CVE-2026-43083 is a Critical severity Linux kernel vulnerability with a CVSS score of 9.1 out of 10 , classified as an Out-of-bounds Read flaw (CWE-125) . It affects Linux kernel versions from 5.17 onward and has been patched in 6.18.24, 6.19.14 and 7.0. CVE-2026-43083 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2026-43083?
CVE-2026-43083 has a CVSS score of 9.1 out of 10, rated Critical severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H. -
Is there a patch available for CVE-2026-43083?
Yes — CVE-2026-43083 has been patched. Fixed versions include 6.18.24, 6.19.14 and 7.0. If you are running Linux kernel 5.17 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-43083 actively exploited?
No — CVE-2026-43083 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
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What is Out-of-bounds Read (CWE-125)?
The product reads data past the end or before the beginning of the intended buffer. View CWE-125 on MITRE CWE →