Junglewise Threat Intelligence

CVE-2026-43094: Linux Kernel ixgbevf NULL pointer dereference in Hyper-V

CVE-2026-43094 · Severity: medium · CVSS 5.5 · Published 2026-05-06

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability in the Linux kernel's Intel network driver affects virtual machines running on Microsoft Hyper-V. When the system attempts to initialize the network interface, it may encounter a critical error that causes the operating system to crash. This results in a denial-of-service, potentially disrupting business operations and service availability on affected virtual servers.

Technical details

A NULL pointer dereference exists in the ixgbevf driver within the Linux kernel when operating on Hyper-V virtual machines. The vulnerability is caused by a missing '.negotiate_features' callback in the 'ixgbevf_hv_mac_ops' table. During the driver probe process, 'ixgbevf_negotiate_api()' calls 'ixgbevf_set_features()', which unconditionally dereferences this function pointer. A local attacker or a system process triggering a device probe can cause a kernel panic (DoS). The issue has been resolved by adding a proper handler that returns -EOPNOTSUPP, which the caller handles gracefully. Patches are available for multiple stable kernel branches including 6.1, 6.6, 6.12, 6.18, and 6.19.

Affected products

  • Linux Linux Kernel 6.1.158 to 6.2, 6.6.114 to 6.6.136, 6.12.55 to 6.12.83, 6.17.5 to 6.18, 6.18.1 to 6.18.24, 6.19 to 6.19.14

Timeline

  • 2026-05-06: advisory: Initial disclosure by kernel.org
  • 2026-05-06: disclosed
  • 2026-04-22: patched: Fixes committed to stable trees

References

Related threats