An unauthenticated server-side request forgery vulnerability in BidingCC BuildingAI allows remote attackers to perform internal network reconnaissance or access sensitive metadata.

The vulnerability exists in the remote upload endpoint, specifically within the uploadRemoteFile function in file-storage.service.ts. The application fails to validate the destination URL against internal network ranges, allowing an unauthenticated attacker to coerce the server into making arbitrary outbound HTTP requests.

Successful exploitation of this flaw can lead to severe operational risks, including the exposure of internal-only services, cloud metadata endpoints, and sensitive configuration data. While the CVSS score of 7.3 reflects the base severity, the ability for an unauthenticated actor to perform reconnaissance against internal infrastructure significantly elevates the risk to enterprise confidentiality and system integrity.

Immediate Action: As no official patch is currently available, administrators should immediately disable the public remote upload endpoint if it is not business-critical.

Proactive Monitoring: Security teams should monitor egress traffic logs for anomalous requests originating from the BuildingAI server to internal IP addresses or sensitive cloud metadata services (e.g., 169.254.169.254).

Compensating Controls: Deploy a Web Application Firewall (WAF) to filter and block requests to the /upload/remote endpoint that contain internal, private, or loopback IP addresses in the URL parameter.

Public Exploit Available: Yes, a published proof-of-concept exists and is attributed to the research write-up linked in the GitHub issue tracker for the project.

Given the availability of a public proof-of-concept and the lack of a vendor-provided fix, this vulnerability presents a credible risk to internal network security. Organizations currently running BuildingAI should prioritize isolating the affected service or implementing strict network egress controls to prevent the server from reaching internal resources until a formal security update is released.