Security readout for executives and security teams
Plain-English summary
CVE-2023-21674 is a Windows privilege escalation flaw in ALPC. An attacker with low-privileged local access could gain high-impact control over confidentiality, integrity, and availability. CISA lists it as known exploited, so this should be treated as an active risk for affected Windows fleets.
Executive priority
High priority. This is not a remote entry point by itself, but known exploitation means it can turn an initial Windows foothold into broader compromise. Patch affected Windows systems through normal emergency vulnerability processes, especially shared endpoints and servers.
Technical view
The source bundle identifies a CWE-416 use-after-free in Windows Advanced Local Procedure Call. CVSS 3.1 is 8.8 with local attack vector, low complexity, low privileges required, no user interaction, changed scope, and high CIA impact. Microsoft is the authoritative remediation source.
Likely exposure
Exposure is likely on unpatched affected Microsoft Windows versions listed in the bundle, including Windows 8.1, Windows 10, Windows 11, and Windows Server 2012 R2 through 2022 variants. Exploitation requires local low-privileged access, so compromised users, shared systems, and servers allowing interactive access matter most.
Exploitation context
CISA KEV inclusion supports known exploitation in the wild. The bundle does not provide exploit details, campaign attribution, or telemetry. Because this is local elevation of privilege, it is most relevant after an attacker already has a foothold on a Windows host.
Researcher notes
The public bundle confirms ALPC EoP, CWE-416, CVSS 8.8, affected Windows versions, and KEV status. It does not include root-cause details, exploit primitives, indicators of compromise, or exact patch KB mappings. Use MSRC for authoritative product-specific remediation.
Mitigation direction
- Apply the Microsoft security updates referenced by the MSRC advisory.
- Prioritize affected Windows endpoints and servers with interactive or shared access.
- Verify unsupported or legacy Windows versions have vendor-supported remediation available.
- Limit local logon rights and remove unnecessary low-privileged accounts.
- Monitor Microsoft and CISA guidance for updated remediation direction.
Validation and detection
- Inventory Windows versions against the affected product list in the source bundle.
- Confirm the relevant Microsoft security update is installed on each affected host.
- Review vulnerability scanner results for CVE-2023-21674 coverage.
- Check EDR and Windows logs for suspicious local privilege escalation behavior.
- Validate high-risk servers do not permit unnecessary interactive user access.
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-416: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupPrivilege 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-2023-21674 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:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:F/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.
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:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C26Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:F/RL:O/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- Windows Advanced Local Procedure Call (ALPC) Elevation of Privilege VulnerabilityCVE reference · vendor-advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-21674CVE 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.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.