Service interruption via unclamped HID report size
Published Apr 24, 2026 · Updated Apr 24, 2026
Undefined shift handling in the Linux Kernel HID core allows local users to interrupt service through a malformed HID report descriptor. The HID core's s32ton() shifts a 32-bit value by report_size minus one after the parser accepts sizes through 256, causing undefined shifts when hid_output_field() or hid_set_field() builds output. Triggering requires local access to present a crafted HID descriptor and affects availability, with no evidenced data disclosure or modification.
Summary
What happened
Undefined shift handling in the Linux Kernel HID core allows local users to interrupt service through a malformed HID report descriptor. The HID core's s32ton() shifts a 32-bit value by report_size minus one after the parser accepts sizes through 256, causing undefined shifts when hid_output_field() or hid_set_field() builds output. Triggering requires local access to present a crafted HID descriptor and affects availability, with no evidenced data disclosure or modification.
The record
- CVE
- CVE-2026-31624
- Published
- Apr 24, 2026
- Updated
- Apr 24, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 24, 2026CVE publishedPublication date reported by the CVE source.
- Apr 24, 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?
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- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <58386f00af710922cafb0fb69211497beddfaa95
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <8a8333237f1f5caab8d4c3d2c2e7578c4263a97f
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <97014719bb8fccb1ffcbbc299e84b1f11b114195
- Affected versionversion=1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 <ea363a34086ddb4231adc581a7f36c39ec154bfc
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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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