Device reset via uninitialized credential-store mutex
Published Aug 12, 2026 · Updated Aug 12, 2026
Denial of service in Zephyr RTOS 3.2.0 through 4.4.1 allows remote attackers to reset devices through concurrent TLS handshakes. credential_lock is declared as a zero-filled k_mutex, leaving its wait queue uninitialized so contention makes sys_dlist_append dereference a NULL tail. Exposure requires CONFIG_TLS_CREDENTIALS_BACKEND_PROTECTED_STORAGE and simultaneous credential access; the resulting kernel panic resets the device without confidentiality or integrity loss.
Summary
What happened
Denial of service in Zephyr RTOS 3.2.0 through 4.4.1 allows remote attackers to reset devices through concurrent TLS handshakes. credential_lock is declared as a zero-filled k_mutex, leaving its wait queue uninitialized so contention makes sys_dlist_append dereference a NULL tail. Exposure requires CONFIG_TLS_CREDENTIALS_BACKEND_PROTECTED_STORAGE and simultaneous credential access; the resulting kernel panic resets the device without confidentiality or integrity loss.
The record
- CVE
- CVE-2026-12233
- Published
- Aug 12, 2026
- Updated
- Aug 12, 2026
- Vendor
- Zephyr Project
- Product
- Zephyr RTOS
- Classifications
- CWE-665, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Aug 12, 2026CVE publishedPublication date reported by the CVE source.
- Aug 12, 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=3.2.0 <4.4.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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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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