Security readout for executives and security teams
Plain-English summary
CVE-2021-31943 is a high-severity remote code execution issue in Microsoft 3D Viewer. A successful attack could let code run with serious confidentiality, integrity, and availability impact, but the source data indicates user interaction is required and does not show active exploitation.
Executive priority
Treat as a standard high-priority workstation patching item, not an emergency zero-day response based on current evidence. Prioritize broad endpoint remediation and exception tracking.
Technical view
The CVSS 3.1 vector is 7.8: AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. The bundle identifies Microsoft 3D Viewer 7.0.0 as affected. Remediation is listed as official, but the provided sources do not include detailed fix mechanics.
Likely exposure
Exposure is most likely on endpoints where Microsoft 3D Viewer 7.0.0 is installed or usable. Risk is higher where users may open untrusted 3D content or file attachments.
Exploitation context
The bundle marks KEV as false and CVSS exploit maturity as unproven. Do not treat this as confirmed active exploitation based on these sources. The attack model requires local access context and user interaction.
Researcher notes
Evidence is limited to Microsoft, CVE, and CVSS metadata. The sources identify impact and affected product but do not describe root cause, file formats, attack details, or specific fixed versions.
Mitigation direction
- Apply Microsoft’s official update or guidance for CVE-2021-31943.
- Inventory endpoints for Microsoft 3D Viewer 7.0.0.
- Remove or restrict 3D Viewer where it is not business-required.
- Warn users against opening unexpected 3D Viewer content.
- Prioritize managed workstations and high-value user groups first.
Validation and detection
- Confirm 3D Viewer version status through endpoint inventory.
- Check vulnerability scanner findings for CVE-2021-31943 closure.
- Verify Microsoft guidance has been applied on affected assets.
- Review whether 3D Viewer remains installed where unnecessary.
- Document any exceptions with owner and target remediation date.
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.
Execution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-31943 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
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
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.
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:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31943CVE reference · x_refsource_MISC
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.