Uninitialized sensor-data disclosure via positive SCSI errors
Published Jan 21, 2025 · Updated May 11, 2026
Improper error handling in the Linux kernel drivetemp driver allows local users to read uninitialized hwmon sensor data after SCSI errors. The driver returns positive scsi_execute_cmd results to hwmon as though they were successful, while hwmon recognizes only negative error values. Reachability requires the drivetemp driver, a managed SCSI disk, and a command error such as drive disconnection; the reported effect is invalid or residual sensor output.
Summary
What happened
Improper error handling in the Linux kernel drivetemp driver allows local users to read uninitialized hwmon sensor data after SCSI errors. The driver returns positive scsi_execute_cmd results to hwmon as though they were successful, while hwmon recognizes only negative error values. Reachability requires the drivetemp driver, a managed SCSI disk, and a command error such as drive disconnection; the reported effect is invalid or residual sensor output.
The record
- CVE
- CVE-2025-21656
- Published
- Jan 21, 2025
- Updated
- May 11, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- Unavailable
- Attack vector
- local
- Privileges
- Unavailable
Timeline
How it unfolded
- Jan 21, 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
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=5.6
- Affected versionversion=5b46903d8bf372e563bf2150d46b87fff197a109 <42268d885e44af875a6474f7bba519cc6cea6a9d
- Affected versionversion=5b46903d8bf372e563bf2150d46b87fff197a109 <53e25b10a28edaf8c2a1d3916fd8929501a50dfc
- Affected versionversion=5b46903d8bf372e563bf2150d46b87fff197a109 <82163d63ae7a4c36142cd252388737205bb7e4b9
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
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Public exploit references
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Technologies
Your stack
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Your stack
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