Attempts to access the server using credentials that have been involved in previous security incidents.

The IP attempted to login to the POP3 server with an invalid username.

Server Side Template Injection: Suspicious input patterns aimed at coercing server-side parsers to execute injected code.

This IP belongs to Telstra.

It attempted zero-day attacks, exploiting unknown vulnerabilities in pop3.

It was responsible for an unusual increase in server CPU usage.

The IP engaged in DNS Spoofing, rerouting our server's lookups to a malicious destination.

Attempts to access the server using stolen or leaked credentials.

Path/File Enumeration: Logs show multiple HTTP requests to non-existing pages and incrementing filenames, suggesting file or path enumeration.

Multiple requests with identical request parameters.

GET /cgi-bin/test.cgi: Could indicate the threat actor is trying to exploit older, less secure scripting interfaces.

The IP attempted to register with the Asterisk server using an invalid username.

It attempted to login to the SSH server with an invalid password.

The IP launched HTTP tunnel attacks, attempting to wrap other protocols in HTTP to bypass network filters.

It attempted to send emails from the Postfix server that violate the server's usage policy.

This IP belongs to Linode.

The malicious IP was seen trying to perform a Replay attack, capturing SIP authentication data and resending it to gain unauthorized access.

This IP belongs to Liberty Mutual Insurance Group.

This IP belongs to Walgreens Boots Alliance.

It made multiple requests with the same X-Requested-With header.

Multiple requests with the same X-UIDH header.

This IP belongs to Dow Chemical.

Multiple requests with the same X-Wap-Profile header.

IP Spoofing: Logs showing HTTP requests with IP ranges that are typically reserved for private networks or an unusual X-Forwarded-For header.

Excessive Form Submission Attempts: Numerous form submission attempts within a short time, signifying brute-force or captcha bypass attempts.