CVE-2026-14366 zephyrproject CVE debrief

Who should care

Defenders responsible for Zephyr-based systems using the SiWx917 WiFi driver should assess exposure and prioritize patching or mitigation. The vulnerability can be triggered by ordinary transmission over the native-stack SiWx917 WiFi interface, and an adjacent attacker on the same WiFi network can induce transmissions to drive the path.

Why it matters

A use-after-free vulnerability in the Silicon Labs SiWx917 WiFi driver's transmit callback siwx91x_send() in the Zephyr operating system can lead to loss of availability and memory corruption. Defenders responsible for Zephyr-based systems using the SiWx917 WiFi driver should assess exposure and prioritize patching or mitigation.

• Loss of availability due to transmit hangs and crashes from pool corruption
• Memory corruption of the kernel networking buffer pool

Technical summary

The Silicon Labs SiWx917 WiFi driver's transmit callback siwx91x_send() in drivers/wifi/siwx91x/siwx91x_wifi.c frees a network packet it does not own. The packet is owned by the L2/networking stack, and the driver only borrows it to copy the frame bytes into a local net_buf. Before the fix, after transmitting, siwx91x_send() additionally called net_pkt_unref(pkt) on the caller-owned packet, dropping its last reference and returning it to the shared packet pool prematurely.

Defensive priority

High

Recommended defensive actions

• Review and apply the fix from the Zephyr project
• Update the SiWx917 WiFi driver to the latest version
• Monitor network activity for potential exploitation
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The vulnerability is caused by the SiWx917 WiFi driver's transmit callback siwx91x_send() freeing a network packet it does not own. The packet is owned by the L2/networking stack, and the driver only borrows it to copy the frame bytes into a local net_buf. The fix removes the erroneous net_pkt_unref(pkt) from siwx91x_send().

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.