Cyber Resilience

CVE-2026-10656

Memory Safety in Zephyrproject Zephyr 4.2.0 – 4.4.0

Public PoCMemory Safety
Published
05 July 2026
Modified
14 July 2026
Patch / advisory
CVSS Score v3.1 4.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0028 20th percentile
Risk Priority 36 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-10656 is a medium-severity NULL Pointer Dereference (CWE-476) vulnerability in Zephyrproject Zephyr. Its CVSS base score is 4.6 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 20th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SA-15 (Development Process, Standards, and Tools) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

The MAX32xxx USB device controller driver (drivers/usb/udc/udc_max32.c, compatible adi_max32_usbhs) dereferenced an endpoint buffer in its OUT and IN transfer-completion handlers without checking it for NULL. udc_event_xfer_out_done() called net_buf_add(buf, ep_request->actlen) immediately after buf = udc_buf_get(ep_cfg), where udc_buf_get() returns NULL when the…

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endpoint FIFO is empty. A transfer-completion event is queued from interrupt context and processed asynchronously by the driver thread; between queuing and processing, the endpoint FIFO can be drained by host-controlled control flow — in particular udc_setup_received() drains the EP0 OUT/IN FIFOs whenever a new SETUP packet arrives, and dequeue/disable/purge paths drain it likewise. A USB host that aborts an in-flight EP0 control transfer with a new SETUP packet (legal USB behavior) can therefore cause a stale XFER_OUT_DONE event to be processed against an empty FIFO, producing net_buf_add(NULL, ...), a near-NULL pointer dereference that faults and crashes the device. No authentication is required; the attacker is the USB host the device is connected to (physical bus access). Impact is denial of service (device crash). 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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
T1489 Service Stop Impact
Adversaries may stop or disable services on a system to render those services unavailable to legitimate users.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-5590Same product: Zephyrproject Zephyr
CVE-2026-10670Same product: Zephyrproject Zephyr
CVE-2026-10648Same product: Zephyrproject Zephyr
CVE-2024-3332Same product: Zephyrproject Zephyr
CVE-2026-10593Same product: Zephyrproject Zephyr
CVE-2023-0779Same product: Zephyrproject Zephyr
CVE-2023-0359Same product: Zephyrproject Zephyr
CVE-2026-10678Same product: Zephyrproject Zephyr
CVE-2026-10674Same product: Zephyrproject Zephyr
CVE-2025-2962Same product: Zephyrproject Zephyr

Affected Assets

zephyrproject
zephyr
4.2.0 — 4.4.0

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation (including static analysis) directly finds null-dereference bugs before deployment.

Documented development standards and tools can enforce null-safety rules and safe pointer usage.

Engineering principles can mandate defensive coding such as explicit null checks before dereference.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References