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CVE Record

CVE-2021-30525: Use after free in TabGroups in Google Chrome prior to 91.0.4472.77 allowed an attacker who convinced a user...

Use after free in TabGroups in Google Chrome prior to 91.0.4472.77 allowed an attacker who convinced a user to install a malicious extension to potentially exploit heap corruption via a crafted HTML page.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2021-30525 is a memory safety flaw in Google Chrome's TabGroups feature. A victim would need to install a malicious extension and then interact with a crafted HTML page. Chrome versions before 91.0.4472.77 are identified as affected. No cited source says this was actively exploited.

Executive priority

Treat this as a routine but important browser update issue, not an emergency zero-day based on the provided evidence. Prioritize older unmanaged endpoints and environments where users can freely install extensions.

Technical view

The CVE describes a use-after-free in Chrome TabGroups that could lead to heap corruption when combined with a malicious extension and crafted HTML. The public record does not provide CVSS, CWE, exploit maturity, or detailed patch mechanics. Google’s stable channel update identifies the fixed Chrome release as 91.0.4472.77.

Likely exposure

Exposure is most likely on endpoints running Google Chrome before 91.0.4472.77. Organizations using distro-packaged browser builds should review the referenced Gentoo and Fedora advisories for package-specific status. Extension installation controls materially affect practical exposure.

Exploitation context

The available sources require user-assisted conditions: convincing a user to install a malicious extension and encounter crafted HTML. The CVE is not listed as KEV in the supplied bundle, and no cited source confirms active exploitation.

Researcher notes

Public detail is limited. The issue class is use-after-free with potential heap corruption, but the supplied sources do not include CVSS, CWE, exploit details, or proof of active exploitation. Avoid assuming impact beyond Chrome before 91.0.4472.77 and referenced vendor package advisories.

Mitigation direction

  • Update Chrome to 91.0.4472.77 or later.
  • Apply relevant Gentoo or Fedora browser package updates where applicable.
  • Review vendor guidance for any package-specific remediation notes.
  • Restrict extension installation to approved sources and approved extensions.
  • Remove unknown or unnecessary extensions from managed endpoints.

Validation and detection

  • Inventory Chrome versions and flag anything before 91.0.4472.77.
  • Confirm distro-managed systems received the referenced advisory updates.
  • Review extension inventory for unapproved or suspicious extensions.
  • Check endpoint management policy for enforced extension allowlisting.
  • Verify browser update controls are working across user groups.
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

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CVE-2021-30525 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
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
GoogleChromeunspecifiedListed
Weakness

CWE details

No CWE listed

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