CVE-2026-43180 Linux CVE debrief

Who should care

Defenders responsible for Linux kernel maintenance and security should assess exposure and prioritize patching to prevent potential URB submission issues. This includes operators, platform administrators, vulnerability management teams, and security teams responsible for maintaining Linux kernel deployments.

Why it matters

A vulnerability in the Linux kernel's kaweth_set_rx_mode function can cause a double usb_submit_urb() on the same URB, leading to a WARN in usb_submit_urb(): 'URB submitted while active'. Defenders should prioritize verifying the Linux kernel version and applying patches to prevent potential URB submission issues.

• Verify Linux kernel versions to determine if vulnerable
• Apply patches to prevent potential URB submission issues
• Review Linux kernel configurations to ensure secure settings
• Monitor Linux kernel updates and patches for future vulnerabilities

Technical summary

The kaweth_set_rx_mode function in the Linux kernel calls netif_stop_queue() and netif_wake_queue(), which are TX queue flow control functions unrelated to RX multicast configuration. This can lead to a double usb_submit_urb() on the same URB, causing a WARN in usb_submit_urb(): 'URB submitted while active'. The vulnerability affects Linux kernel deployments using the kaweth module. Defenders should prioritize verifying the Linux kernel version and applying patches to prevent potential URB submission issues. The real set_rx_mode action is performed by kaweth_async_set_rx_mode(), which in turn is not a no-op only at ndo_open() time.

Defensive priority

Defenders should prioritize verifying the Linux kernel version and applying patches to prevent potential URB submission issues.

Recommended defensive actions

• Verify Linux kernel versions and apply patches to prevent potential URB submission issues
• Review and update Linux kernel configurations to ensure secure settings
• Monitor Linux kernel updates and patches for future vulnerabilities
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE record and source item provide details on the vulnerability, including its description, affected versions, and references to kernel.org stable commits. The source item notes that kaweth_set_rx_mode(), the ndo_set_rx_mode callback, calls netif_stop_queue() and netif_wake_queue(). These are TX queue flow control functions unrelated to RX multicast configuration. The premature netif_wake_queue() can re-enable TX while tx_urb is still in-flight, leading to a double usb_submit_urb() on the same URB.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.