Security readout for executives and security teams
Plain-English summary
A local attacker could exploit a Windows VBS Enclave memory-handling flaw to read sensitive information. No user interaction or prior privileges are required, but the attacker must already be able to execute locally. The issue affects listed Windows 11 23H2, 24H2, and 25H2 releases.
Executive priority
Treat this as a standard but timely endpoint patching priority. Accelerate remediation for shared, high-value, or less-controlled Windows 11 systems because successful exploitation could expose sensitive data without prior privileges or user interaction. Current sources do not support emergency response based on active exploitation.
Technical view
CVE-2026-20935 is a CWE-822 untrusted pointer dereference in Windows Virtualization-Based Security Enclave. Its CVSS 3.1 score is 6.2: local access, low complexity, no privileges or interaction, high confidentiality impact, and no stated integrity or availability impact.
Likely exposure
Potential exposure includes listed Windows 11 23H2 build 22631, 24H2 build 26100, and 25H2 build 26200 systems. Practical risk depends on whether an attacker can execute locally and reach the vulnerable VBS Enclave path. The bundle does not identify additional affected builds or prerequisites.
Exploitation context
The source bundle does not establish active exploitation, and the CVE is not listed as KEV. The CVSS vector marks exploit maturity as unproven. Exploitation requires local access but reportedly needs neither prior privileges nor user interaction, making compromised endpoints and shared systems important exposure contexts.
Researcher notes
The disclosed root cause is an untrusted pointer dereference, but the bundle provides no vulnerable function, attack boundary details, leaked data types, or proof-of-concept evidence. Validate exposure against Microsoft's advisory and avoid assuming all VBS configurations are equally reachable. The duplicate 23H2 product entries appear to describe the same build.
Mitigation direction
- Review Microsoft's CVE advisory for the applicable security update and deployment guidance.
- Apply the Microsoft update to affected Windows 11 systems through approved patch management.
- Prioritize endpoints where untrusted users or processes can execute locally.
- Use normal endpoint controls to restrict unauthorized local code execution pending remediation.
Validation and detection
- Inventory Windows 11 editions, versions, and OS builds across managed endpoints.
- Compare identified systems with the affected 23H2, 24H2, and 25H2 build lines.
- Confirm the Microsoft security update is installed using authoritative patch-management records.
- Review endpoint telemetry for unexpected local execution or sensitive-data access around VBS workloads.
- Recheck Microsoft's advisory for revised affected-build and remediation information.
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-822: 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 lookupCVE-2026-20935 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
- Medium
- CVSS
- 6.2 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/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.
SSVC decision data
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:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C2.53.6microsoftVulnerability scoring details
Base CVSS 3.1 score
6.2MediumVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- Windows Virtualization-Based Security (VBS) Information Disclosure VulnerabilityCVE reference, microsoft · vendor-advisory, patch
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.
Untrusted Pointer Dereference
Untrusted Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.