GHSA-55HM-QVFP-55MJ
Vulnerability from github – Published: 2026-09-11 21:31 – Updated: 2026-09-14 15:32In 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.
{
"affected": [],
"aliases": [
"CVE-2026-89621"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-11T20:19:47Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\nHID: mcp2221: validate report size in mcp2221_raw_event()\n\nmcp2221_raw_event() never validates the size of incoming HID reports.\nIn the MCP2221_I2C_GET_DATA path it trusts the device-supplied data[3]\nas the copy length without checking that 4 + data[3] bytes actually\nexist in the received report. A malicious or misbehaving USB device can\nsend a short report with a large data[3], causing the memcpy to read\npast the valid report data in the HID transfer buffer and leak\nuninitialized kernel memory back to userspace through the I2C/SMBus\nread path.\n\nAdd a minimum size check at entry and validate that the source range\nfits within the received report before the copy.",
"id": "GHSA-55hm-qvfp-55mj",
"modified": "2026-09-14T15:32:32Z",
"published": "2026-09-11T21:31:34Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-89621"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/127de5919820f88a9d55e8371ad4ac49f625f4c5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/2c9a6998c19503626c57a2267bf279e204113079"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/7c18fb36708a97ff6772825cc087b6d537bbf0d5"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/b2c67dc0e30c308647bbd9b9e5d69a44c9d2733d"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/bdc6a3af0dd734a326acdb7d6401a3b6a9f4f149"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/c1c508e8923911cb458234997e55b7a4b9aa066f"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/cb38b1f149b7143355b37e86c841acf0076e5c2a"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/fffcfa367072628c3144cca17d2a3c3c9e50c057"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
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|---|
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