CVE Catalog

CVE-2026-89622

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

5th percentile - higher than 5% of all known CVEs

Summary

In the mcp2221 HID driver, mcp_i2c_smbus_read() stored a buffer pointer in mcp->rxbuf but never cleared it after the transfer completed. A delayed or spurious MCP2221_I2C_GET_DATA report could write data into freed memory.

Risk Assessment

This can lead to a write use-after-free, potentially causing kernel memory corruption, a system crash, or possible code execution.

Recommendation

Update the Linux kernel to a version containing the fix that clears mcp->rxbuf and mcp->rxbuf_size after the I2C/SMBus transfer completes.

Other vulnerabilities in Linux kernel

See all
Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: HID: mcp2221: clear rxbuf after I2C/SMBus transfer completes mcp_i2c_smbus_read() stores the caller-supplied buffer pointer in mcp->rxbuf for the duration of a transfer but never clears it when the transfer finishes or times out. Once the caller frees or reuses the buffer, mcp->rxbuf becomes a dangling pointer. A delayed or spurious MCP2221_I2C_GET_DATA report can then drive mcp2221_raw_event() to memcpy device data into the freed memory, causing a write use-after-free. Route all return paths through a single exit point that clears mcp->rxbuf and mcp->rxbuf_size, so that the existing !mcp->rxbuf guard in the raw_event handler can reject any report arriving after the transfer has ended.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS