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PatchSiren cyber security CVE debrief

CVE-2021-37973 Google CVE debrief

CVE-2021-37973 is a Google Chromium Portals use-after-free vulnerability that CISA added to its Known Exploited Vulnerabilities catalog on 2021-11-03. Because it is listed in KEV, defenders should treat it as a high-priority patching item and apply vendor updates without delay.

Vendor
Google
Product
Chromium Portals
CVSS
Unknown
CISA KEV
Listed
Original CVE published
2021-11-03
Original CVE updated
2021-11-03
Advisory published
2021-11-03
Advisory updated
2021-11-03

Who should care

Security teams and administrators responsible for Chromium-based browser deployments, endpoint patch management, and any environment tracking CISA KEV items. Organizations that rely on Google Chromium components should prioritize validation and deployment of vendor updates.

Technical summary

The issue is identified as a use-after-free in Google Chromium Portals. The supplied official sources confirm the CVE record and that CISA categorized it as a known exploited vulnerability, with a required action to apply updates per vendor instructions. No CVSS score was provided in the supplied data.

Defensive priority

High. CISA KEV inclusion indicates known exploitation and a short remediation window was set in the catalog (date added 2021-11-03, due 2021-11-17). This should be prioritized ahead of routine patch backlog items.

Recommended defensive actions

  • Apply the vendor-recommended update path for affected Chromium-based products and components.
  • Verify which endpoints, browsers, or embedded Chromium builds are exposed to the affected Portals component.
  • Track remediation to completion before the KEV due date and confirm the vulnerable version is removed from inventory.
  • Use the official CVE and NVD records to cross-check internal asset lists and patch status.

Evidence notes

Confirmed facts in the supplied corpus are limited to the CVE identifier, the use-after-free classification, Google Chromium Portals as the affected product, and CISA KEV listing with dateAdded 2021-11-03 and dueDate 2021-11-17. No CVSS score was provided in the source data. The official links included in the corpus are the CVE record, NVD detail page, CISA KEV catalog, and the source JSON feed.

Sources and references

Verified primary and authoritative sources

  • CVE-2021-37973 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2021-37973

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2021-37973 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2021-37973

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

  • CISA Known Exploited Vulnerabilities catalog

    Publisher, destination, and source semantics verified

    URL: https://www.cisa.gov/known-exploited-vulnerabilities-catalog

    Cybersecurity and Infrastructure Security Agency - Official CISA catalog of vulnerabilities known to be exploited in the wild.

Supplemental references

  • Source item URL

    Unverified legacy reference

    URL: https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

    cisa_kev

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.