The ssrfcheck library is vulnerable to Server-Side Request Forgery (SSRF) due to an incomplete input validation list, enabling potential unauthorized requests to internal network resources.

The library fails to adequately sanitize input strings, allowing attackers to bypass SSRF protection mechanisms. This vulnerability is remotely exploitable without authentication, potentially leading to unauthorized interaction with internal services.

An SSRF vulnerability allows an attacker to pivot into an internal network, potentially accessing private APIs, metadata services, or sensitive internal documentation. Given the CVSS score of 8.2, this represents a significant security risk, especially in cloud-hosted environments where internal metadata services (e.g., AWS IMDS) could be exposed.

Immediate Action: Since a specific patch version is currently unavailable, users should consider replacing the library with a more robust alternative or implementing additional input validation/whitelisting logic at the application layer.

Proactive Monitoring: Review outbound network traffic from the application server for unexpected connections to internal IP addresses or sensitive local ports.

Compensating Controls: Restrict the application server's network access via egress filtering/security groups to ensure it can only communicate with required external endpoints and cannot reach sensitive internal infrastructure.

Public Exploit Available: Unknown

Because there is no immediate patch available, developers must exercise caution when using this library. Implementing strict egress filtering and alternative input validation logic is essential to mitigate the risk of internal network exposure until a permanent fix is released.