CVE-2026-31729

Summary

In the Linux kernel, the following vulnerability has been resolved:

usb: typec: ucsi: validate connector number in ucsi_notify_common()

The connector number extracted from CCI via UCSI_CCI_CONNECTOR() is a 7-bit field (0-127) that is used to index into the connector array in ucsi_connector_change(). However, the array is only allocated for the number of connectors reported by the device (typically 2-4 entries).

A malicious or malfunctioning device could report an out-of-range connector number in the CCI, causing an out-of-bounds array access in ucsi_connector_change().

Add a bounds check in ucsi_notify_common(), the central point where CCI is parsed after arriving from hardware, so that bogus connector numbers are rejected before they propagate further.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxbdc62f2bae8fb0e8e99574de5232f0a3c54a27df < f6dcbf2b024d55549959402f1db6c614e51d52cbaffected
LinuxLinuxbdc62f2bae8fb0e8e99574de5232f0a3c54a27df < f4e608fe12b7ac6a4a57176ab0296bb5a110a078affected
LinuxLinuxbdc62f2bae8fb0e8e99574de5232f0a3c54a27df < 98429e9ec89a5e3a204112dfaa2dbe6ca28493a0affected
LinuxLinuxbdc62f2bae8fb0e8e99574de5232f0a3c54a27df < d2d8c17ac01a1b1f638ea5d340a884ccc5015186affected
LinuxLinux5.5affected
LinuxLinux0 < 5.5unaffected
LinuxLinux6.12.81 <= 6.12.*unaffected
LinuxLinux6.18.22 <= 6.18.*unaffected
LinuxLinux6.19.12 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References