System hang via unlocked TCPM state check
Published Jul 10, 2025 · Updated May 11, 2026
Improper locking in Linux kernel TCPM allows local users to hang affected systems through a DisplayPort Alt Mode race. The unprotected state check in tcpm_queue_vdm_unlocked can pass before TCPM changes state while holding tcpm_lock, leaving DisplayPort Alt Mode work waiting on that lock as TCPM waits in cancel_work_sync. Exploitation requires local low-privileged access and a USB Type-C DisplayPort Alt Mode transition during the narrow race window; the resulting deadlock interrupts system availability.
Summary
What happened
Improper locking in Linux kernel TCPM allows local users to hang affected systems through a DisplayPort Alt Mode race. The unprotected state check in tcpm_queue_vdm_unlocked can pass before TCPM changes state while holding tcpm_lock, leaving DisplayPort Alt Mode work waiting on that lock as TCPM waits in cancel_work_sync. Exploitation requires local low-privileged access and a USB Type-C DisplayPort Alt Mode transition during the narrow race window; the resulting deadlock interrupts system availability.
The record
- CVE
- CVE-2025-38268
- Published
- Jul 10, 2025
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- CWE-667, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 10, 2025CVE publishedPublication date reported by the CVE source.
- May 11, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=6.9
- Affected versionversion=cdc9946ea6377e8e214b135ccc308c5e514ba25f <1970d34b48cbeceb0c765984c9a6bb204c77f16a
- Affected versionversion=cdc9946ea6377e8e214b135ccc308c5e514ba25f <324d45e53f1a36c88bc649dc39e0c8300a41be0a
- Affected versionversion=cdc9946ea6377e8e214b135ccc308c5e514ba25f <7bdd712abefbec79176ab412d8c623e755c5d0ba
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo