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CVE Record

CVE-2021-3669: A flaw was found in the Linux kernel.

A flaw was found in the Linux kernel. Measuring usage of the shared memory does not scale with large shared memory segment counts which could lead to resource exhaustion and DoS.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

CVE-2021-3669 is a Linux kernel resource-exhaustion issue involving shared memory usage measurement. Systems with many shared memory segments could spend excessive resources accounting for them, causing denial of service. The supplied sources do not provide CVSS, affected kernel versions, or confirmed exploitation.

Executive priority

Treat as a kernel DoS risk requiring vendor confirmation, not an emergency based on supplied evidence. Prioritize patch review for critical Linux infrastructure and shared compute environments.

Technical view

The flaw is categorized as CWE-400. The CVE description says shared memory usage measurement does not scale with large segment counts, which can lead to resource exhaustion and DoS. Product/version scope is listed only as Linux kernel with versions not known.

Likely exposure

Potential exposure is Linux systems running affected kernel builds, but the supplied bundle does not identify exact versions, configurations, or distributions. Confirm status through vendor trackers, especially Red Hat and Debian references.

Exploitation context

The source bundle marks KEV as false and provides no cited evidence of active exploitation. It also does not state attack vector, required privileges, or exploit maturity.

Researcher notes

Evidence is sparse: no CVSS, no affected version range, and no attack-vector detail are supplied. Analysis should stay anchored to vendor trackers and the CVE description until distribution-specific advisories clarify impact.

Mitigation direction

  • Check Red Hat and Debian trackers for affected and fixed kernel package status.
  • Apply vendor-provided kernel security updates when this CVE is listed.
  • Prioritize shared or multi-tenant Linux systems if vendor exposure is confirmed.
  • Monitor vendor advisories for version-specific mitigations or backports.

Validation and detection

  • Inventory Linux kernel versions across servers, containers hosts, and appliances.
  • Compare installed kernel packages against Red Hat or Debian CVE tracker status.
  • Confirm whether security update records mention CVE-2021-3669.
  • Document systems where vendor status remains unknown.
Prepared
Confidence
medium
Sources
7

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.

cwe · low confidence lookup

CWE-400: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2021-3669 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
0Timeline events
0ADP providers
6Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/akernelNot KnownListed
Weakness

CWE details

CWE-400

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

CWE-400 · source CWE mapping

CWE mapping pending import

This CVE carries a CWE mapping that will resolve to a full Glexia CWE intelligence page after the official CWE import is complete.

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