CVE-2026-43083 in the critical feed json
net: ioam6: fix OOB and missing lock
published 2026-05-06 6 mo ago modified 2026-10-30 9 d ago also EUVD-2026-27576
- cvss
- 9.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 48%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Linux Linux 6.1.191, 6.6.160, 6.12.114, 6.18.24, 6.19.14, 7.0
- linux Debian 13 6.12.115-2
- linux Debian 14 6.19.14-1
debian advisories DEBIAN-CVE-2026-43083
- linux Ubuntu 24.04 LTS 6.8.0-137.137
- linux Ubuntu 25.10 6.17.0-40.40
- linux-aws Ubuntu 24.04 LTS 6.8.0-1062.65
- linux-aws Ubuntu 25.10 6.17.0-1019.19
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1065.73
- linux-gcp Ubuntu 25.10 6.17.0-1020.22
- linux-gke Ubuntu 24.04 LTS 6.8.0-1060.68
- linux-ibm Ubuntu 24.04 LTS 6.8.0-1062.63
ubuntu advisories UBUNTU-CVE-2026-43083
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-syms SLES 16.0, Linux Micro Extras 6.2, SLES for SAP applications 16.0 6.12.0-160000.36.1
- kernel-obs-build Linux Micro Extras 6.2 6.12.0-160000.36.1
- kernel-rt Linux Micro 6.2 6.12.0-160000.36.1
- kernel-64kb SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.36.1
- kernel-source SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.36.1
- kernel-default SLES 16.0, SLE High Availability Extension 16.0, Linux Micro 6.2 +1 more 6.12.0-160000.36.1
- kernel-default-base SLES 16.0, Linux Micro 6.2, SLES for SAP applications 16.0 6.12.0-160000.36.1.160000.2.17
- kernel-azure SLES for SAP applications 16.0, SLES 16.0 6.12.0-160000.36.1
suse advisories SUSE-SU-2026:22742-1SUSE-SU-2026:22769-1SUSE-SU-2026:22835-1SUSE-SU-2026:22812-1SUSE-SU-2026:2799-1SUSE-SU-2026:2722-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.36.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.36.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.36.1
opensuse advisories openSUSE-SU-2026:21388-1
- git.kernel.org/stable/c/d8fa972c543e6a41f9a0873a725fd1d8d4d9dbfc commit
- git.kernel.org/stable/c/a05a85779c2574b6534abb8cdc6d65fbc2e91208 commit
- git.kernel.org/stable/c/f1af9d19503b73011dae5051c354fd39b03e240d commit
- git.kernel.org/stable/c/6d1d9ed9b409e0662241e3d245d574a18f643494 commit
- git.kernel.org/stable/c/95a1334748c95dd15546056280ade0c4b8dd7b78 commit
- git.kernel.org/stable/c/b30b1675aa2bcf0491fd3830b051df4e08a7c8ca commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-43083 updated cvss 5.5
kernel: net: ioam6: fix OOB and missing lock
-
Red Hat Enterprise Linux 10 kernelaffected: no fix available “Fix deferred”
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 morenot affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 23 d ago
Exploit prediction
0.60% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H |
Affected products
- Linux Linux
Classification
- Weakness
-
- CWE-125 Out-of-bounds Read
- Technology feeds
References
- git.kernel.org /stable/c/d8fa972c543e6a41f9a0873a725fd1d8d4d9dbfc
- git.kernel.org /stable/c/a05a85779c2574b6534abb8cdc6d65fbc2e91208
- git.kernel.org /stable/c/f1af9d19503b73011dae5051c354fd39b03e240d
-
git.kernel.org
/stable/c/6d1d9ed9b409e0662241e3d245d574a18f643494
patch
-
git.kernel.org
/stable/c/95a1334748c95dd15546056280ade0c4b8dd7b78
patch
-
git.kernel.org
/stable/c/b30b1675aa2bcf0491fd3830b051df4e08a7c8ca
patch
Sources
- CVE List CVE-2026-43083
- NVD CVE-2026-43083
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