Security readout for executives and security teams
Plain-English summary
CVE-2021-31170 is a high-severity Windows Graphics Component privilege escalation flaw. It does not appear to be a remote entry point by itself, but a local attacker or malware with low privileges could potentially gain much broader control on affected Windows systems.
Executive priority
Treat as high priority for normal patch operations, especially on servers and multi-user endpoints. Escalate if vulnerable systems are exposed to untrusted local users or already suspected of compromise.
Technical view
The CVSS 3.1 vector is AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H, scoring 7.8. The provided sources identify Microsoft Windows Graphics Component as affected across several Windows 10 and Windows Server releases. No CWE is listed in the source bundle.
Likely exposure
Exposure is likely on unpatched affected Windows 10 versions 1803, 1809, 1909, 2004, 20H2 and related Windows Server releases listed by Microsoft/NVD-derived data.
Exploitation context
The source bundle says CISA KEV is false and CVSS exploit maturity is unproven. No cited source in the bundle states active exploitation. The risk is mainly local privilege escalation after an attacker or malware has code execution as a low-privileged user.
Researcher notes
The bundle provides severity, affected products, CVSS, MSRC, and ZDI references, but not root-cause detail, exploit primitives, or KB identifiers. Avoid assuming exploitation or exact fix packages without consulting vendor advisory content.
Mitigation direction
- Apply Microsoft security updates for CVE-2021-31170 from the MSRC advisory.
- Prioritize internet-facing servers, shared workstations, and systems allowing local user logon.
- Check Microsoft guidance for exact supported build and KB applicability.
- Reduce local administrative access while patch rollout completes.
- Retire unsupported affected Windows builds where updates are unavailable.
Validation and detection
- Inventory Windows builds against the affected product list in the source bundle.
- Confirm installed Microsoft security updates include the CVE-2021-31170 fix.
- Review vulnerability scanner results for this CVE on endpoints and servers.
- Check patch compliance separately for Server Core installations.
- Document exceptions and verify Microsoft guidance for each exception.
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.
Privilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-31170 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:L/UI:N/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:L/UI:N/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:L/UI:N/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-2021-31170CVE reference · x_refsource_MISC
- https://www.zerodayinitiative.com/advisories/ZDI-21-578/CVE 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.