Security readout for executives and security teams
Plain-English summary
A flaw in Azure Virtual Network Gateway could let an already-authorized attacker run code remotely. Successful exploitation could expose data, alter systems, or interrupt availability across a security boundary. The 9.9 CVSS score makes this critical, but the supplied sources do not identify affected versions or tenant-specific exposure.
Executive priority
Treat this as an immediate validation and remediation priority because compromise could have broad confidentiality, integrity, and availability consequences. Require accountable owners to confirm exposure and Microsoft-directed remediation promptly. Do not claim compromise solely because a gateway exists.
Technical view
CVE-2026-40411 is an improper input validation vulnerability, classified as CWE-20. The CVSS vector indicates network access, low attack complexity, low privileges, no user interaction, changed scope, and high confidentiality, integrity, and availability impact. Exact vulnerable versions and technical attack conditions are not provided.
Likely exposure
Organizations using Azure Virtual Network Gateway may be exposed, but the supplied version field is unspecified. Exposure cannot be confirmed from product presence alone. Determine whether Microsoft identifies each gateway, configuration, region, or service state as affected.
Exploitation context
The attacker must be authorized, according to the CVE description, but only low privileges are reflected in the CVSS vector. The supplied bundle marks KEV as false and provides no evidence of active exploitation. Exploit maturity is recorded as unproven.
Researcher notes
Public details are limited to the weakness class, authorization requirement, and CVSS characteristics. Affected versions are unspecified, and no technical indicators, attack chain, or detailed remediation are included in the bundle. Avoid assuming which authorization boundary or gateway configuration is required.
Mitigation direction
- Review the Microsoft advisory for the required remediation or service action.
- Inventory all Azure Virtual Network Gateway deployments and responsible owners.
- Apply Microsoft’s prescribed update or mitigation wherever the advisory identifies exposure.
- Restrict gateway administration and related permissions to necessary identities.
- Increase monitoring for unusual gateway access or configuration activity.
Validation and detection
- Confirm every gateway against the scope defined in Microsoft’s advisory.
- Verify Microsoft’s prescribed remediation is complete for each affected deployment.
- Review identity assignments for unnecessary gateway-related privileges.
- Check relevant Azure logs for anomalous access or configuration changes.
- Document gateways whose exposure remains uncertain and escalate them to Microsoft support.
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-20: 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-40411 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
- Critical
- CVSS
- 9.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/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.
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:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C3.16microsoftVulnerability scoring details
Base CVSS 3.1 score
9.9CriticalVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/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
- Azure Virtual Network Gateway Remote Code Execution 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.