Local service interruption via timestamp-mask shift
Published Oct 24, 2025 · Updated Oct 24, 2025
Shift-out-of-bounds in the Linux peak_usb CAN driver allows local users to interrupt service through a PC CAN FD interface. The peak_usb_update_ts_now function forms a timestamp-wrap mask by shifting the 32-bit integer literal 1 by ts_used_bits, which equals 32 for affected adapters. Reaching the faulty shift requires a 32-bit kernel, local low-privileged access, and supported PC CAN FD hardware.
Summary
What happened
Shift-out-of-bounds in the Linux peak_usb CAN driver allows local users to interrupt service through a PC CAN FD interface. The peak_usb_update_ts_now function forms a timestamp-wrap mask by shifting the 32-bit integer literal 1 by ts_used_bits, which equals 32 for affected adapters. Reaching the faulty shift requires a 32-bit kernel, local low-privileged access, and supported PC CAN FD hardware.
The record
- CVE
- CVE-2025-40020
- Published
- Oct 24, 2025
- Updated
- Oct 24, 2025
- Vendor
- The Linux Kernel Organization
- Product
- Linux
- Classifications
- T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 24, 2025CVE publishedPublication date reported by the CVE source.
- Oct 24, 2025Record 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=3.4
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <176c81cbf9c4e348610a421aad800087c0401f60
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <17edec1830e48c0becd61642d0e40bc753243b16
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <394c58017e5f41043584c345106cae16a4613710
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <48822a59ecc47d353400d38b1941d3ae7591ffff
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <572c656802781cc57f4a3231eefa83547e75ed78
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <61b1dd4c614935169d12bdecc26906e37b508618
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <c443be70aaee42c2d1d251e0329e0a69dd96ae54
- Affected versionversion=bb4785551f64e18b2c8bb15a3bd2b22f5ebf624d <eb79ed970670344380e77d62f8188e8015648d94
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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