In the Linux kernel, the following vulnerability has been resolved:
HID: mcp2221: validate report size in mcp2221_raw_event()
mcp2221_raw_event() never validates the size of incoming HID reports.
In the MCP2221_I2C_GET_DATA path it trusts the device-supplied data[3]
as the copy length without checking that 4 + data[3] bytes actually
exist in the received report. A malicious or misbehaving USB device can
send a short report with a large data[3], causing the memcpy to read
past the valid report data in the HID transfer buffer and leak
uninitialized kernel memory back to userspace through the I2C/SMBus
read path.
Add a minimum size check at entry and validate that the source range
fits within the received report before the copy.
HID: mcp2221: validate report size in mcp2221_raw_event()
mcp2221_raw_event() never validates the size of incoming HID reports.
In the MCP2221_I2C_GET_DATA path it trusts the device-supplied data[3]
as the copy length without checking that 4 + data[3] bytes actually
exist in the received report. A malicious or misbehaving USB device can
send a short report with a large data[3], causing the memcpy to read
past the valid report data in the HID transfer buffer and leak
uninitialized kernel memory back to userspace through the I2C/SMBus
read path.
Add a minimum size check at entry and validate that the source range
fits within the received report before the copy.
Metrics
Affected Vendors & Products
Advisories
| Source | ID | Title |
|---|---|---|
Debian DLA |
DLA-4817-1 | linux-6.12 security update |
Debian DLA |
DLA-4841-1 | linux security update |
Debian DSA |
DSA-6528-1 | linux security update |
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Mon, 14 Sep 2026 12:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Sat, 12 Sep 2026 15:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-119 CWE-200 |
Sat, 12 Sep 2026 12:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-125 | |
| References |
| |
| Metrics |
threat_severity
|
cvssV3_1
|
Sat, 12 Sep 2026 09:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Weaknesses | CWE-119 CWE-200 |
Fri, 11 Sep 2026 23:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: HID: mcp2221: validate report size in mcp2221_raw_event() mcp2221_raw_event() never validates the size of incoming HID reports. In the MCP2221_I2C_GET_DATA path it trusts the device-supplied data[3] as the copy length without checking that 4 + data[3] bytes actually exist in the received report. A malicious or misbehaving USB device can send a short report with a large data[3], causing the memcpy to read past the valid report data in the HID transfer buffer and leak uninitialized kernel memory back to userspace through the I2C/SMBus read path. Add a minimum size check at entry and validate that the source range fits within the received report before the copy. | |
| Title | HID: mcp2221: validate report size in mcp2221_raw_event() | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Projects
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Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-10-19T08:49:53.686Z
Reserved: 2026-09-11T19:38:34.736Z
Link: CVE-2026-89621
No data.
Status : Received
Published: 2026-09-11T20:19:47.397
Modified: 2026-10-19T09:17:58.880
Link: CVE-2026-89621
OpenCVE Enrichment
Updated: 2026-09-15T21:15:14Z
Weaknesses
Debian DLA
Debian DSA