Memory corruption via non-atomic net_buf reference counts
Published Jun 30, 2026 · Updated Jun 30, 2026
Double free in the net_buf library in Zephyr Project Zephyr RTOS 2.7.0 through 4.4.0 allows attackers to corrupt memory via a race. Plain increments and decrement-and-test operations let concurrent net_buf_unref callers both observe the same prior reference count and free or recycle one buffer twice. Exploitation requires genuine concurrency and an application that shares one buffer among independent unref callers; packet content does not directly trigger the race.
Summary
What happened
Double free in the net_buf library in Zephyr Project Zephyr RTOS 2.7.0 through 4.4.0 allows attackers to corrupt memory via a race. Plain increments and decrement-and-test operations let concurrent net_buf_unref callers both observe the same prior reference count and free or recycle one buffer twice. Exploitation requires genuine concurrency and an application that shares one buffer among independent unref callers; packet content does not directly trigger the race.
The record
- CVE
- CVE-2026-10653
- Published
- Jun 30, 2026
- Updated
- Jun 30, 2026
- Vendor
- Zephyr Project
- Product
- Zephyr RTOS
- Classifications
- CWE-415
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 30, 2026CVE publishedPublication date reported by the CVE source.
- Jun 30, 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=2.7.0 <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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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