Security readout for executives and security teams
Plain-English summary
This is a Windows privilege-escalation flaw in the Container Isolation FS Filter Driver. An attacker who already has low-privileged local access could potentially gain high-impact control over confidentiality, integrity, and availability on affected Windows systems.
Executive priority
Prioritize remediation in normal high-severity Windows patch cycles, with faster handling for shared servers and container hosts. This is not evidenced as actively exploited, but it can worsen the impact of any existing foothold.
Technical view
CVE-2021-31190 is a local elevation-of-privilege vulnerability affecting Microsoft Windows 10 Version 1809, Windows Server 2019, and Server Core installations. CVSS 3.1 is 7.8: local attack vector, low complexity, low privileges required, no user interaction, and high CIA impact.
Likely exposure
Exposure is most relevant to affected Windows 10 1809 and Windows Server 2019 systems, including Server Core. The driver name suggests special attention for Windows container hosts, but the source bundle does not define container-use prerequisites.
Exploitation context
The bundle does not show CISA KEV listing or cited evidence of active exploitation. CVSS marks exploit maturity as unproven. Treat it as a serious post-compromise escalation risk rather than an internet-facing initial-access issue.
Researcher notes
Available public details are sparse. The strongest source-grounded facts are Microsoft attribution, affected Windows versions, CVSS vector, official remediation status, and no KEV evidence. Avoid assuming exploit availability, vulnerable code paths, or exact container configuration requirements from the title alone.
Mitigation direction
- Apply Microsoft’s official security update for CVE-2021-31190 on affected Windows builds.
- Check MSRC guidance for applicable KBs and platform-specific remediation details.
- Prioritize Windows Server 2019 systems hosting containers or shared workloads.
- Retire or isolate unsupported affected Windows builds where patching is not possible.
Validation and detection
- Inventory Windows 10 1809 and Windows Server 2019 assets, including Server Core.
- Confirm installed build and patch state against Microsoft’s CVE advisory.
- Review vulnerability scanner findings for CVE-2021-31190 on Windows endpoints and servers.
- Verify container hosts are included in patch compliance reporting.
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 lookupContainer behavior lookup
The affected technology mentions containers, so container-specific ATT&CK technique review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-31190 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-2021-31190CVE 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.