---
id: CVE-2025-71108
title: 'usb: typec: ucsi: Handle incorrect num_connectors capability'
summary: |-
  In the Linux kernel, the following vulnerability has been resolved:

  usb: typec: ucsi: Handle incorrect num_connectors capability

  The UCSI spec states that the num_connectors field is 7 bits, and the
  8th bit is reserved and should be se…
severity: none
vendor: Linux
product: Linux
affected:
  - >-
    Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f <
    07c8d2a109d847775b3b4e2c3294c8e1eea75432
  - >-
    Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f <
    58941bbb0050e365a98c64f1fc4a9a0ac127dba6
  - >-
    Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f <
    f72f97d0aee4a993a35f2496bca5efd24827235d
  - >-
    Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f <
    914605b0de8128434eafc9582445306830748b93
  - >-
    Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f <
    3042a57a8e8bce4a3100c3f6f03dc372aab24943
  - >-
    Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f <
    132fe187e0d940f388f839fe2cde9b84106ad20d
  - >-
    Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f <
    30cd2cb1abf4c4acdb1ddb468c946f68939819fb
  - Linux 4.13
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-06-10T20:41:26.190531Z'
published: '2026-01-14'
updated: '2026-10-19'
sourceUpdated: '2026-10-19T18:15:13.504Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2025-71108'
references:
  - url: 'https://git.kernel.org/stable/c/07c8d2a109d847775b3b4e2c3294c8e1eea75432'
  - url: 'https://git.kernel.org/stable/c/58941bbb0050e365a98c64f1fc4a9a0ac127dba6'
  - url: 'https://git.kernel.org/stable/c/f72f97d0aee4a993a35f2496bca5efd24827235d'
  - url: 'https://git.kernel.org/stable/c/914605b0de8128434eafc9582445306830748b93'
  - url: 'https://git.kernel.org/stable/c/3042a57a8e8bce4a3100c3f6f03dc372aab24943'
  - url: 'https://git.kernel.org/stable/c/132fe187e0d940f388f839fe2cde9b84106ad20d'
  - url: 'https://git.kernel.org/stable/c/30cd2cb1abf4c4acdb1ddb468c946f68939819fb'
tags:
  - cve.org
epss: 0.00147
epssPercentile: 0.0353
ingestedAt: '2026-10-19T18:35:50.135Z'
---

## Overview

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

usb: typec: ucsi: Handle incorrect num_connectors capability

The UCSI spec states that the num_connectors field is 7 bits, and the
8th bit is reserved and should be set to zero.
Some buggy FW has been known to set this bit, and it can lead to a
system not booting.
Flag that the FW is not behaving correctly, and auto-fix the value
so that the system boots correctly.

Found on Lenovo P1 G8 during Linux enablement program. The FW will
be fixed, but seemed worth addressing in case it hit platforms that
aren't officially Linux supported.

## Affected

- `Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f < 07c8d2a109d847775b3b4e2c3294c8e1eea75432`
- `Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f < 58941bbb0050e365a98c64f1fc4a9a0ac127dba6`
- `Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f < f72f97d0aee4a993a35f2496bca5efd24827235d`
- `Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f < 914605b0de8128434eafc9582445306830748b93`
- `Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f < 3042a57a8e8bce4a3100c3f6f03dc372aab24943`
- `Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f < 132fe187e0d940f388f839fe2cde9b84106ad20d`
- `Linux >= c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f < 30cd2cb1abf4c4acdb1ddb468c946f68939819fb`
- `Linux 4.13`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.