The security analyst should recommend replacing the strcpy function with a safer alternative. The strcpy function is a C library function that copies a string from one buffer to another. However, this function does not check the size of the destination buffer, which can lead to buffer overflow vulnerabilities if the source string is longer than the destination buffer. Buffer overflow vulnerabilities can allow attackers to execute arbitrary code or crash the program. A safer alternative to strcpy is strncpy, which limits the number of characters copied to the size of the destination buffer.

Threat hunting is a proactive process of searching for signs of malicious activity or compromise within a system or network, by using hypotheses, indicators of compromise, and analytical tools. Threat hunting can help improve detection capabilities by identifying unknown threats, uncovering gaps in security controls, and providing insights for remediation and prevention. Vulnerability scanning (A) is a reactive process of scanning systems or networks for known vulnerabilities or weaknesses that can be exploited by attackers. It can help identify and prioritize vulnerabilities, but not proactively hunt for threats. Red teaming is a simulated attack on a system or network by a group of ethical hackers who act as adversaries and try to breach security controls. It can help test the effectiveness of security defenses and response capabilities, but not proactively hunt for threats. Penetration testing (D) is similar to red teaming, but with a more defined scope and objective. It can help evaluate the security of a system or network by simulating real-world attacks and exploiting vulnerabilities, but not proactively hunt for threats.

Sinkholing is a technique for manipulating data flow in a network; you redirect traffic from its intended destination to a server of your choosing.It can be used maliciously, to steer legitimate traffic away from its intended recipient, but security professionals more commonly use sinkholing as a tool for research and reacting to attacks1.

For example, sinkholing can be used to redirect traffic from a botnet or a malware-infected host to a server under the control of the defender, where the traffic can be analyzed, blocked, or neutralized.This can help identify and isolate compromised devices, prevent command-and-control communication, and disrupt malicious activities2.

The other options are not the best solutions for the following reasons:

Blocklisting is a technique for preventing access to or communication with certain IP addresses, domains, or applications that are known or suspected to be malicious. Blocklisting can be implemented using firewalls, routers, proxies, or software tools. Blocklisting can protect a network from unwanted or harmful traffic, but it does not redirect the traffic to a different destination.

Geoblocking is a technique for restricting access to or communication with certain IP addresses, domains, or applications based on their geographic location. Geoblocking can be implemented using firewalls, routers, proxies, or software tools. Geoblocking can protect a network from unauthorized or undesirable traffic from specific regions or countries, but it does not redirect the traffic to a different destination.

Sandboxing is a technique for isolating and executing potentially malicious code or applications in a separate and secure environment. Sandboxing can be implemented using virtual machines, containers, or software tools. Sandboxing can protect a network from malware infection or damage, but it does not redirect the network traffic to a different destination.

The security analyst needs to investigate further the source IP address 10.50.180.49. This IP address belongs to a private network that is not routable on the internet. However, the firewall usage report shows that this IP address has sent traffic to an external destination on port 443 (HTTPS). This could indicate that the IP address is spoofed or compromised by an attacker who is using it to exfiltrate data or communicate with a command-and-control server.

The security analyst should implement a control that uses built-in functions from libraries to check and handle long numbers properly. This will help prevent integer overflow vulnerabilities, which occur when a value is moved into a variable type too small to hold it. For example, if an integer variable can only store values up to 255, and a value of 256 is assigned to it, the variable will overflow and wrap around to 0.This can cause unexpected program behavior or lead to buffer overflow vulnerabilities if the overflowed value is used as an index or size for memory allocation1.Built-in functions from libraries can help avoid integer overflow by performing checks on the input values and the resulting values, and throwing exceptions or errors if they exceed the limits of the variable type2.