CVE-2026-43094: ixgbevf: add missing negotiate_features op to Hyper-V ops table
In the Linux kernel, the following vulnerability has been resolved:
ixgbevf: add missing negotiatefeatures op to Hyper-V ops table
Commit a7075f501bd3 ("ixgbevf: fix mailbox API compatibility by negotiating supported features") added the .negotiatefeatures callback to ixgbemacoperations and populated it in ixgbevfmacops, but forgot to add it to ixgbevfhvmacops. This leaves the function pointer NULL on Hyper-V VMs.
During probe, ixgbevfnegotiateapi() calls ixgbevfsetfeatures(), which unconditionally dereferences hw->mac.ops.negotiatefeatures(). 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 workforcpufn RIP: 0010:0x0 [...] Call Trace: ixgbevfnegotiateapi+0x66/0x160 [ixgbevf] ixgbevfswinit+0xe4/0x1f0 [ixgbevf] ixgbevfprobe+0x20f/0x4a0 [ixgbevf] localpciprobe+0x50/0xa0 workforcpufn+0x1a/0x30 [...]
Add ixgbevfhvnegotiatefeaturesvf() that returns -EOPNOTSUPP and wire it into ixgbevfhvmacops. The caller already handles -EOPNOTSUPP gracefully.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-43094?
The severity of CVE-2026-43094 is classified as moderate due to potential operational issues in Hyper-V environments.
How do I fix CVE-2026-43094?
To fix CVE-2026-43094, you should apply the latest patches or updates to the ixgbevf driver in your Linux kernel.
What are the potential impacts of CVE-2026-43094?
The potential impacts of CVE-2026-43094 include impaired communication between virtual machines and physical network devices in Hyper-V setups.
Is CVE-2026-43094 exploitable remotely?
CVE-2026-43094 is not considered exploitable remotely as it primarily affects local Hyper-V configurations.
Which software versions are affected by CVE-2026-43094?
CVE-2026-43094 affects specific versions of the ixgbevf driver within the Linux kernel, particularly those prior to applying the relevant patches.