LiveActive security incident?Get immediate response
CVE Record

CVE-2021-46948: sfc: farch: fix TX queue lookup in TX event handling

In the Linux kernel, the following vulnerability has been resolved: sfc: farch: fix TX queue lookup in TX event handling We're starting from a TXQ label, not a TXQ type, so efx_channel_get_tx_queue() is inappropriate (and could return NULL, leading to panics).

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

Security readout for executives and security teams

Plain-English summary

This Linux kernel issue can cause a system panic when handling certain transmit queue events in the sfc driver path. A panic can interrupt service availability, but the provided sources do not describe data theft, privilege escalation, or active exploitation.

Executive priority

Treat this as an availability-focused kernel maintenance item. Prioritize exposed network-facing or production hosts using the sfc driver, but escalation to emergency response is not supported by the provided evidence.

Technical view

The bug is in Linux kernel sfc farch TX event handling. Code starts from a TXQ label but used efx_channel_get_tx_queue(), which expects a TXQ type and could return NULL, leading to kernel panics. Upstream stable commits resolve the lookup logic.

Likely exposure

Exposure appears limited to Linux systems running the affected kernel versions or commits and using the relevant sfc driver path. The source bundle does not confirm affected distributions, hardware models, or whether default configurations are reachable.

Exploitation context

CISA KEV is false in the provided bundle, and no cited source reports active exploitation. The documented outcome is a possible panic from a NULL queue lookup during TX event handling, suggesting availability risk rather than confirmed compromise.

Researcher notes

Evidence is concise and kernel-focused. The root cause is a queue lookup mismatch: TXQ label versus TXQ type. The bundle lacks CVSS, CWE, exploitability details, affected distro advisories, and precise operational prerequisites.

Mitigation direction

  • Update affected Linux kernels through the relevant vendor or distribution channel.
  • Prioritize systems using the sfc driver or matching network hardware path.
  • Check whether vendor kernels include one of the referenced upstream stable fixes.
  • Avoid direct deployment changes until testing confirms driver and network stability.

Validation and detection

  • Inventory Linux kernel versions against the affected version list in the CVE record.
  • Identify hosts using the sfc driver path or related network adapters.
  • Confirm the kernel build includes the referenced stable fix commits.
  • Review system logs for unexplained kernel panics involving sfc TX event handling.
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

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-2021-46948 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
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
LinuxLinux12804793b17c0e19115a90d98f2f3df0cb79e233, 12804793b17c0e19115a90d98f2f3df0cb79e233, 12804793b17c0e19115a90d98f2f3df0cb79e233, 12804793b17c0e19115a90d98f2f3df0cb79e233unaffected
LinuxLinux5.10, 0, 5.10.36, 5.11.20, 5.12.3, 5.13affected
Weakness

CWE details

No CWE listed

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