LiveActive security incident?Get immediate response
CVE Record

CVE-2025-71108: usb: typec: ucsi: Handle incorrect num_connectors capability

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.

UnknownCVSS not scoredNot KEV-listedUpdated
Discuss exposureBack to CVEs
Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2025-71108 is a Linux kernel USB Type-C/UCSI issue where some incorrect firmware data can prevent a system from booting. It was found on a Lenovo P1 G8 during Linux enablement. The business risk is availability disruption on specific hardware and firmware combinations, not a confirmed remote attack path.

Executive priority

Treat as a targeted availability issue. Prioritize affected Linux workstation fleets, hardware enablement programs, and systems with recent boot failures. It is not currently supported as an internet-scale exploitation emergency by the provided sources.

Technical view

The UCSI num_connectors capability is defined as 7 bits, with the 8th bit reserved. Some firmware sets the reserved bit. A Linux kernel fix detects the bad firmware behavior and masks the value so boot can continue. The CVE record lists Linux kernel exposure beginning with 4.13 and stable fixes across multiple kernel branches.

Likely exposure

Most likely limited to Linux systems using affected kernel builds with USB Type-C/UCSI firmware that reports the reserved bit incorrectly. The source specifically names Lenovo P1 G8 as observed, but says other unofficially supported platforms could be affected.

Exploitation context

No cited source reports active exploitation, and the CVE is not in KEV. The known trigger is buggy firmware behavior rather than a documented attacker-controlled path. Impact is system boot failure, creating availability risk for affected endpoints or workstations.

Researcher notes

Evidence is limited to the CVE record and Linux stable commits. No CVSS, CWE, exploitability analysis, or distribution-specific package status is provided. Downstream exposure depends on kernel branch, backports, and platform firmware behavior.

Mitigation direction

  • Update Linux kernels through vendor-supported packages that include the referenced stable fixes.
  • Check OEM firmware guidance for affected hardware, especially Lenovo P1 G8-class systems.
  • Prioritize remediation for systems showing boot failures during Linux deployment or updates.

Validation and detection

  • Inventory Linux endpoints using USB Type-C/UCSI support.
  • Compare deployed kernel builds against vendor advisories and the referenced stable commits.
  • Review boot failure reports for UCSI or Type-C initialization errors.
  • Confirm OEM firmware versions against hardware vendor guidance when available.
Prepared
Confidence
medium
Sources
9

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cve · low confidence lookup

CVE-2025-71108 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
3Timeline events
1ADP providers
8Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: partial

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  2. CVE publishedCVE Program

    The CVE record was published.

  3. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinuxc1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f, c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f, c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f, c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f, c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f, c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2f, c1b0bc2dabfa884dea49c02adaf3cd6b52b33d2funaffected
LinuxLinux4.13, 0, 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.3, 6.19affected
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.