Security readout for executives and security teams
Plain-English summary
Chrome’s V8 JavaScript engine had a memory corruption flaw before version 95.0.4638.69. A malicious web page could trigger it if a user visited the page, potentially compromising browser confidentiality, integrity, and availability. CISA lists CVE-2021-38003 as known exploited, so old unmanaged browsers are the business concern.
Executive priority
Treat as urgent hygiene for endpoint fleets because it is high severity and CISA-listed as known exploited. Prioritize unmanaged, legacy, and Linux desktop/browser package exposure.
Technical view
CVE-2021-38003 is an inappropriate implementation issue in V8 leading to potential heap corruption through crafted HTML. The CVSS 3.1 score is 8.8 with network attack vector, low complexity, no privileges required, and user interaction required. Public sources name Google Chrome prior to 95.0.4638.69 and downstream Chromium packages in Debian and Fedora advisories.
Likely exposure
Exposure is most likely on endpoints running Chrome or Chromium-based distribution packages that were not updated after the October 2021 Chrome stable release or relevant Linux vendor advisories.
Exploitation context
CISA KEV listing confirms this CVE is known exploited. The provided sources do not describe exploit chains, affected platforms beyond Chrome and downstream packages, or current campaign details.
Researcher notes
The source bundle supports heap corruption in V8 via crafted HTML with user interaction. It does not provide public bug details from crbug, exploit indicators, or a standalone workaround beyond updating through Google or distro packages.
Mitigation direction
- Update Chrome to 95.0.4638.69 or later, preferably the current stable version.
- Apply Debian and Fedora Chromium security updates where those packages are used.
- Remove or isolate unsupported browsers that cannot receive security updates.
- Check current vendor guidance for any environment-specific remediation notes.
Validation and detection
- Inventory Chrome and Chromium versions across managed endpoints.
- Confirm no Chrome installations remain below 95.0.4638.69.
- Verify Debian and Fedora Chromium packages include the relevant security fixes.
- Review browser crash telemetry for unexplained Chrome or V8 crashes around risky browsing activity.
- Confirm patch compliance through endpoint management or vulnerability scanning records.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-755: Exact CWE lookup
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Open ATT&CK lookupCVE-2021-38003 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 8.8 (3.1)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
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.
CISA KEV status
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.8HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://chromereleases.googleblog.com/2021/10/stable-channel-update-for-desktop_28.htmlCVE reference · x_refsource_MISC
- https://crbug.com/1263462CVE reference · x_refsource_MISC
- FEDORA-2021-6a292e2cf4CVE reference · vendor-advisory, x_refsource_FEDORA
- DSA-5046CVE reference · vendor-advisory, x_refsource_DEBIAN
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-38003CVE reference · government-resource
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Handling of Exceptional Conditions
Improper Handling of Exceptional Conditions represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.