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CVE Record

CVE-2021-47522: HID: bigbenff: prevent null pointer dereference

In the Linux kernel, the following vulnerability has been resolved: HID: bigbenff: prevent null pointer dereference When emulating the device through uhid, there is a chance we don't have output reports and so report_field is null.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2021-47522 is a Linux kernel issue in the BigBen force-feedback HID driver. Under uhid-based device emulation, the driver can hit a missing output-report condition and dereference a null pointer. The public record does not provide CVSS, CWE, or confirmed exploitation, so urgency should be based on kernel exposure and local device-emulation risk.

Executive priority

Treat this as a targeted kernel maintenance issue, not an internet-scale emergency based on current evidence. Prioritize patching on Linux endpoints or specialized systems that allow local device emulation or HID attachment.

Technical view

The flaw is a null pointer dereference in hid-bigbenff when report_field can be null because output reports are absent during uhid emulation. The vulnerability is marked resolved in Linux stable commits. The available source data names Linux kernel versions and commits but does not provide a complete distro-level package matrix or exploitability analysis.

Likely exposure

Exposure appears limited to Linux systems running affected kernels with the BigBen force-feedback HID driver reachable, particularly where uhid device emulation is available. Public source data does not identify specific distributions, appliances, or cloud images.

Exploitation context

The source bundle does not show CISA KEV listing or any cited active exploitation. Based on the described null pointer dereference, the most plausible concern is kernel stability or denial of service, but impact is not scored in the provided sources.

Researcher notes

Key missing evidence includes CVSS scoring, CWE assignment, exact affected version ranges by distribution, and exploitability details. Validate using the kernel stable commits and downstream vendor backports rather than assuming upstream version numbers map directly to packages.

Mitigation direction

  • Apply vendor kernel updates containing the referenced Linux stable fixes.
  • Check distribution advisories for CVE-2021-47522 package status.
  • Restrict uhid access where device emulation is not operationally required.
  • Review whether BigBen HID support is needed on production systems.

Validation and detection

  • Inventory Linux kernel versions against vendor advisories for this CVE.
  • Confirm deployed kernels include the referenced stable commits or equivalent backports.
  • Check whether uhid is enabled and accessible to untrusted users.
  • Identify hosts with HID/game-controller support exposed beyond normal desktop use.
Prepared
Confidence
medium
Sources
6

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

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CVE-2021-47522 mapping review

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

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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
2ADP providers
5Source 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
CVECVE Program Container

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
LinuxLinux256a90ed9e46b270bbc4e15ef05216ff049c3721, 256a90ed9e46b270bbc4e15ef05216ff049c3721, 256a90ed9e46b270bbc4e15ef05216ff049c3721, 256a90ed9e46b270bbc4e15ef05216ff049c3721unaffected
LinuxLinux4.20, 0, 5.4.165, 5.10.85, 5.15.8, 5.16affected
Weakness

CWE details

No CWE listed

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