Physical device crash via unchecked endpoint buffer
Published Jul 5, 2026 · Updated Jul 5, 2026
NULL-pointer dereference in Zephyr RTOS 4.4.0 allows physically proximate attackers to crash devices through crafted USB control transfers. The MAX32 transfer-completion handlers remove an endpoint buffer without checking whether an asynchronously drained FIFO returned NULL, then pass that pointer to net_buf_add. Physical USB-host access is required, and a new SETUP packet can drain EP0 before a stale completion event is processed, faulting the device without exposing or modifying data.
Summary
What happened
NULL-pointer dereference in Zephyr RTOS 4.4.0 allows physically proximate attackers to crash devices through crafted USB control transfers. The MAX32 transfer-completion handlers remove an endpoint buffer without checking whether an asynchronously drained FIFO returned NULL, then pass that pointer to net_buf_add. Physical USB-host access is required, and a new SETUP packet can drain EP0 before a stale completion event is processed, faulting the device without exposing or modifying data.
The record
- CVE
- CVE-2026-10656
- Published
- Jul 5, 2026
- Updated
- Jul 5, 2026
- Vendor
- Zephyr Project
- Product
- Zephyr RTOS
- Classifications
- CWE-476, T1499
- Attack vector
- physical
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 5, 2026CVE publishedPublication date reported by the CVE source.
- Jul 5, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=4.2.0 <4.5.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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