LiveActive security incident?Get immediate response
CVE Record

CVE-2021-47122: net: caif: fix memory leak in caif_device_notify

In the Linux kernel, the following vulnerability has been resolved: net: caif: fix memory leak in caif_device_notify In case of caif_enroll_dev() fail, allocated link_support won't be assigned to the corresponding structure. So simply free allocated pointer in case of error

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

Analyst readout for executives and security teams

Plain-English summary

CVE-2021-47122 is a Linux kernel memory leak in the CAIF networking code. When device enrollment fails, allocated memory may not be released. The public record does not provide CVSS scoring, confirmed exploitation, or business-impact details, so urgency depends on whether affected Linux kernels and CAIF support exist in your fleet.

Executive priority

Handle through routine kernel patch governance unless CAIF-enabled or custom Linux systems are business-critical. There is no provided evidence of exploitation or severe impact, but kernel memory leaks can affect availability if reachable.

Technical view

The issue is in caif_device_notify: if caif_enroll_dev() fails, the allocated link_support object is not attached to the target structure and was not freed. Linux stable fixes add cleanup on that error path. The source bundle identifies affected Linux kernel version ranges and stable commit references, but does not describe exploit prerequisites.

Likely exposure

Exposure is limited to Linux systems running affected kernel builds with the relevant CAIF networking code present. The bundle does not identify distributions, default configurations, or whether ordinary remote traffic can trigger the failure path.

Exploitation context

No active exploitation is cited. The CVE is not listed as KEV in the provided bundle, and no source here claims public exploitation. Treat this as a kernel reliability and resource-exhaustion concern until vendor guidance clarifies practical reachability.

Researcher notes

Key uncertainty is reachability: the sources describe the failed enrollment cleanup bug but not attacker control, privilege requirements, or trigger conditions. Validation should focus on kernel lineage, CAIF presence, and whether the stable fix is included downstream.

Mitigation direction

  • Check distribution kernel advisories for CVE-2021-47122 status.
  • Apply Linux stable or vendor kernel updates containing the referenced fixes.
  • Prioritize systems where CAIF support is enabled or custom kernels are used.
  • Track remediation through normal kernel patch management.

Validation and detection

  • Inventory Linux kernel versions across servers, appliances, and embedded systems.
  • Confirm whether deployed kernels include the referenced stable fix commits.
  • Check kernel configuration or modules for CAIF networking support.
  • Review vendor advisories before assigning production impact.
Prepared
Confidence
medium
Sources
10

Public sources used

Based on public source material and reviewed before publication.

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-2021-47122 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
9Source 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
LinuxLinux7c18d2205ea76eef9674e59e1ecae4f332a53e9e, 7c18d2205ea76eef9674e59e1ecae4f332a53e9e, 7c18d2205ea76eef9674e59e1ecae4f332a53e9e, 7c18d2205ea76eef9674e59e1ecae4f332a53e9e, 7c18d2205ea76eef9674e59e1ecae4f332a53e9e, 7c18d2205ea76eef9674e59e1ecae4f332a53e9e, 7c18d2205ea76eef9674e59e1ecae4f332a53e9e, 7c18d2205ea76eef9674e59e1ecae4f332a53e9eunaffected
LinuxLinux3.3, 0, 4.4.272, 4.9.272, 4.14.236, 4.19.194, 5.4.125, 5.10.43, 5.12.10, 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.