CVE-2026-43094
MediumIn the Linux kernel, the following vulnerability has been resolved: ixgbevf: add missing negotiate_features op to Hyper-V ops table Commit a7075f501bd3 ("ixgbevf: fix mailbox API compatibility by negotiating supported features") added the .negotiate_features callback to ixgbe_mac_operations and populated it in ixgbevf_mac_ops, but forgot to add it to ixgbevf_hv_mac_ops. This leaves the function pointer NULL on Hyper-V VMs. During probe, ixgbevf_negotiate_api() calls ixgbevf_set_features(), which unconditionally dereferences hw->mac.ops.negotiate_features(). On Hyper-V this results in a NULL pointer dereference: BUG: kernel NULL pointer dereference, address: 0000000000000000 [...] Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine [...] Workqueue: events work_for_cpu_fn RIP: 0010:0x0 [...] Call Trace: ixgbevf_negotiate_api+0x66/0x160 [ixgbevf] ixgbevf_sw_init+0xe4/0x1f0 [ixgbevf] ixgbevf_probe+0x20f/0x4a0 [ixgbevf] local_pci_probe+0x50/0xa0 work_for_cpu_fn+0x1a/0x30 [...] Add ixgbevf_hv_negotiate_features_vf() that returns -EOPNOTSUPP and wire it into ixgbevf_hv_mac_ops. The caller already handles -EOPNOTSUPP gracefully.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Weakness type
CWE-476CVE-2026-43094 is a NULL Pointer Dereference vulnerability
What is NULL Pointer Dereference?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE
Affected versions
Linux kernel versions
6.1.158,
6.6.114,
6.12.55,
6.17.5,
6.18
and later are affected. Fixed in
6.1.175,
6.6.136,
6.12.83,
6.18.24,
6.19.14,
7.0
and their respective stable series.
References
The following references provide additional information about CVE-2026-43094 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/1455ff8809843e6e83f1f5b5c0bcc2224c99a3cb
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PatchKernel patch commithttps://git.kernel.org/stable/c/2270ebab53128fb73c4a70a292be09094074737f
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PatchKernel patch commithttps://git.kernel.org/stable/c/376d74ea03589914fbe2dedcbebf418396c04fd0
Frequently asked questions
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What is CVE-2026-43094?
CVE-2026-43094 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 6.1.158 onward and has been patched in 6.1.175, 6.6.136, 6.12.83 and others. CVE-2026-43094 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-2026-43094?
CVE-2026-43094 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2026-43094?
Yes — CVE-2026-43094 has been patched. Fixed versions include 6.1.175, 6.6.136, 6.12.83 and others. If you are running Linux kernel 6.1.158 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2026-43094 actively exploited?
No — CVE-2026-43094 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 NULL Pointer Dereference (CWE-476)?
The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →