Security readout for executives and security teams
Plain-English summary
CVE-2021-31183 is a Windows TCP/IP driver flaw that can cause denial of service. It is important because it is network-reachable, requires no authentication or user interaction, and can affect core Windows servers and workstations. The cited sources describe availability impact only, not data theft or code execution.
Executive priority
Prioritize remediation where Windows availability is business-critical or network exposure is high. This is not sourced as active exploitation, but the unauthenticated network attack surface and high availability impact justify prompt patch validation.
Technical view
Microsoft rates this as a Windows TCP/IP Driver Denial of Service vulnerability with CVSS 3.1 score 7.5. The vector is AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H, meaning remote network access, low complexity, no privileges, no user interaction, and high availability impact.
Likely exposure
Exposure is likely on affected Windows client and server versions listed by Microsoft, especially internet-facing systems, DMZ hosts, VPN-adjacent infrastructure, and critical internal Windows servers. The bundle includes Windows 7, 8.1, multiple Windows 10 releases, and Windows Server 2008 through 2019 variants.
Exploitation context
The provided data does not show CISA KEV listing or active exploitation. The CVSS temporal metric marks exploit maturity as unproven. Treat this as a disruption risk, not confirmed exploitation, unless separate telemetry or vendor updates indicate otherwise.
Researcher notes
The source bundle does not include CWE, packet-level root cause, exploit procedure, or specific KB mappings. Do not infer RCE or confidentiality impact. Validation should focus on affected build identification, MSRC update status, and exposure of Windows TCP/IP attack surface.
Mitigation direction
- Review the Microsoft MSRC advisory for the applicable update path.
- Apply Microsoft-provided security updates to affected Windows builds.
- Prioritize externally reachable and business-critical Windows systems.
- Retire or isolate unsupported legacy Windows systems where patching is not feasible.
- Limit unnecessary network exposure to Windows hosts pending remediation.
Validation and detection
- Inventory Windows versions and build numbers across servers and endpoints.
- Compare assets against the affected product list and CPE build data.
- Confirm Microsoft security updates are installed on matching systems.
- Check vulnerability scanner results for CVE-2021-31183 after patching.
- Review outage monitoring for unexplained availability events on exposed Windows hosts.
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.
CVE-2021-31183 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
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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-2021-31183CVE 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.