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CVE Record

CVE-2021-47184: i40e: Fix NULL ptr dereference on VSI filter sync

In the Linux kernel, the following vulnerability has been resolved: i40e: Fix NULL ptr dereference on VSI filter sync Remove the reason of null pointer dereference in sync VSI filters. Added new I40E_VSI_RELEASING flag to signalize deleting and releasing of VSI resources to sync this thread with sync filters subtask. Without this patch it is possible to start update the VSI filter list after VSI is removed, that's causing a kernel oops.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2021-47184 is a Linux kernel flaw in the i40e driver path. A race during VSI filter synchronization can dereference a null pointer after VSI resources are removed, causing a kernel oops. The main business risk shown by the sources is service disruption, not confirmed data theft or remote compromise.

Executive priority

Handle as a reliability-focused kernel update item. Escalate priority for production network hosts that use the affected i40e driver path, because a kernel oops can disrupt service availability.

Technical view

The resolved kernel bug adds an I40E_VSI_RELEASING flag to coordinate VSI resource teardown with the sync filters subtask. Without that guard, the driver can update a VSI filter list after the VSI has been removed, producing a NULL pointer dereference and kernel oops.

Likely exposure

Exposure is most relevant to Linux systems running affected kernel builds where the i40e driver and VSI filter synchronization path are in use. The source lists affected Linux versions and stable commit references, but does not provide CVSS, CPEs, or deployment conditions.

Exploitation context

The CVE source does not report active exploitation, and KEV is false. The bundle does not describe a public exploit, attacker prerequisites, or whether the condition is locally or remotely triggerable. Treat exploitation evidence as incomplete.

Researcher notes

The available evidence supports a kernel NULL pointer dereference during resource teardown and filter sync. Severity metadata is missing, and the source bundle does not establish exploitability, privileges required, or remote reachability. Validation should focus on kernel lineage and driver presence.

Mitigation direction

  • Identify kernels containing the referenced stable fixes.
  • Update affected Linux kernels through the normal vendor-supported channel.
  • Prioritize systems where i40e driver outages would affect production traffic.
  • Check distribution advisories for backported fixes and package names.
  • Avoid assuming non-listed mitigations without vendor confirmation.

Validation and detection

  • Inventory Linux kernel versions across servers and appliances.
  • Confirm whether the i40e driver is loaded or packaged on exposed systems.
  • Map running kernels against vendor advisories or referenced stable commits.
  • Review logs for kernel oops events involving i40e or VSI filter sync.
  • Verify updated systems boot the expected fixed kernel.
Prepared
Confidence
medium
Sources
8

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-2021-47184 mapping review

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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
7Source 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
LinuxLinux41c445ff0f482bb6e6b72dcee9e598e20575f743, 41c445ff0f482bb6e6b72dcee9e598e20575f743, 41c445ff0f482bb6e6b72dcee9e598e20575f743, 41c445ff0f482bb6e6b72dcee9e598e20575f743, 41c445ff0f482bb6e6b72dcee9e598e20575f743, 41c445ff0f482bb6e6b72dcee9e598e20575f743unaffected
LinuxLinux3.12, 0, 4.14.256, 4.19.218, 5.4.162, 5.10.82, 5.15.5, 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.