A critical authentication bypass and path traversal vulnerability in IoTSharp is currently being actively exploited in the wild.

The application fails to apply authorization requirements to the BlobStorageController, permitting unauthenticated attackers to access sensitive endpoints. Furthermore, improper input sanitization on file paths allows for arbitrary file system access, including the potential for remote code execution via web shell upload.

This vulnerability carries a CVSS score of 9.8, reflecting its critical severity. Successful exploitation allows unauthorized actors to read, modify, or delete sensitive data, and potentially gain full control over the host system. Given its inclusion in the CISA Known Exploited Vulnerabilities (KEV) catalog, the urgency for remediation is extreme to prevent data breaches or total system compromise.

Immediate Action: Update to the latest version of IoTSharp as soon as it is made available by the vendor to implement mandatory authorization checks and path sanitization.

Proactive Monitoring: Review application and web server access logs for requests targeting the BlobStorageController or unusual file path patterns that suggest directory traversal attempts.

Compensating Controls: Deploy a Web Application Firewall (WAF) with rules configured to block directory traversal sequences (such as double dots and slashes) and restrict access to the BlobStorageController endpoints.

Public Exploit Available: Unknown

Due to confirmed active exploitation in the wild, organizations must prioritize this vulnerability immediately. Apply the latest available vendor security updates and monitor network traffic for signs of compromise until patching is complete.