Description

A weakness has been identified in SpecterOps BloodHound up to 9.5.1. The affected element is the function NewV2API of the file cmd/api/src/api/registration/v2.go of the component Graph Write Endpoint. Executing a manipulation can lead to improper authorization. It is possible to launch the attack remotely. Upgrading to version 9.6.0-rc1, 9.6.0 and 9.7.0-rc3 is sufficient to fix this issue. This patch is called 39d1276a63e95a7713f954dea632a19651d9cebb. You should upgrade the affected component.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.3",
  "pubDate": "2026-09-03T23:17:20.807Z",
  "pubdate": "2026-09-03T23:17:20.807Z",
  "executiveSummary": "A critical security weakness has been identified in SpecterOps BloodHound versions up to and including 9.5.1, specifically within the Graph Write Endpoint.\nThe vulnerability is classified as an improper authorization flaw, which allows unauthorized actors to perform operations that should be restricted to authenticated or privileged users.\nThe flaw resides in the NewV2API function, facilitating remote exploitation without requiring complex prerequisites from the attacker.\nSuccessful exploitation allows an attacker to bypass intended security controls, potentially leading to unauthorized data manipulation or modification within the BloodHound database graph.\nGiven the nature of BloodHound as an attack surface mapping tool, unauthorized write access to the graph represents a significant security risk, as it could permit the injection of malicious or misleading relationship data to obfuscate actual attack paths or misdirect administrative remediation efforts.\nThe vulnerability is addressed by updating to the recommended versions: 9.6.0-rc1, 9.6.0, or 9.7.0-rc3.",
  "technicalDetails": "The vulnerability is located in the cmd/api/src/api/registration/v2.go file, specifically within the NewV2API function responsible for handling requests to the Graph Write Endpoint.\nThe root cause of this vulnerability is an improper implementation of authorization checks within the API registration logic, which fails to correctly validate the permissions of a requesting entity before granting access to graph mutation operations.\nThe attack flow involves a remote actor interacting with the Graph Write API exposed by the BloodHound server. Because the validation logic within NewV2API is insufficient, an attacker can craft specifically formatted requests that circumvent the intended access control mechanisms.\nBy manipulating the API request, an attacker can invoke functions that modify the graph structure. This does not necessarily require the attacker to possess valid administrative credentials if the underlying authorization middleware is bypassed during the initialization of the v2 API endpoints.\nWhen the NewV2API function processes an incoming request, the lack of strict authorization enforcement means that the application fails to verify whether the caller has the appropriate scope or role-based access control (RBAC) permissions required for graph write operations.\nThe impact of this vulnerability is severe, as the integrity of the graph database is fundamental to the security posture of the environment BloodHound is auditing. An attacker could inject false relationships, create unauthorized nodes, or delete critical security data. By injecting fabricated attack paths, an attacker could potentially influence security analysts or administrators, leading them to misinterpret the security posture of the Active Directory environment.\nThis vulnerability is present in all versions of SpecterOps BloodHound up to 9.5.1. The flaw is addressed by the patch 39d1276a63e95a7713f954dea632a19651d9cebb, which implements the necessary authorization logic within the endpoint registration process to ensure that only authorized users can perform write operations to the graph database.\nThe exploitation is performable remotely over a network, requiring only connectivity to the BloodHound API endpoint. Once the authorization check is bypassed, the attacker essentially gains an administrative interface into the graph management layer, enabling post-exploitation activities such as graph data exfiltration or persistence mechanism obfuscation."
}