CVE-2026-10656 Zephyrproject CVE debrief

Who should care

Organizations using Zephyr v4.4.0 with MAX32xxx USB device controllers should apply patches to prevent device crashes. Additionally, operators managing these systems, platform administrators, and security teams should be aware of the vulnerability's impact and take necessary precautions. This includes reviewing system inventories, monitoring for suspicious USB activity, and ensuring that affected systems are updated or mitigated.

Technical summary

The MAX32xxx USB device controller driver (drivers/usb/udc/udc_max32.c) dereferenced an endpoint buffer in its OUT and IN transfer-completion handlers without checking it for NULL. A USB host that aborts an in-flight EP0 control transfer with a new SETUP packet can cause a stale XFER_OUT_DONE event to be processed against an empty FIFO, producing a near-NULL pointer dereference that faults and crashes the device. The fix involves adding NULL checks in the transfer-completion handlers to handle such scenarios gracefully.

Defensive priority

High

Recommended defensive actions

• Apply patches from Zephyr project
• Inventory and check affected systems
• Monitor for suspicious USB activity
• 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
• Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The defect was introduced when the MAX32 UDC driver was added and shipped in Zephyr v4.4.0. The fix adds NULL-buffer checks that return early with UDC_EVT_ERROR/-ENOBUFS in both the OUT-done and IN-done handlers. This information is based on the CVE record and NVD detail. Further verification is recommended to confirm affected scope and vendor guidance, including reviewing system logs for related events and checking for updated patches or advisories from the Zephyr project.

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.