Which method is most effective for a pentester to avoid detection when executing a payload?

The choice of compressing and encrypting the payload with a packing tool is effective for avoiding detection when executing a payload in a penetration test. This method combines two crucial elements: compression and encryption.

Compression reduces the size of the payload, which can make it less conspicuous during transmission or when being analyzed by security tools. This smaller footprint can help evade detection by intrusion detection systems (IDS) and other security mechanisms that may flag larger, suspicious payloads.

Encryption further secures the payload by obfuscating its contents, making it unreadable to anyone who intercepts it without the proper decryption key. Many security solutions perform signature-based detection, so if the payload is encrypted, it would not match known malicious signatures, thus slipping past these defenses.

In contrast, while encoding the payload in base64, splitting it into multiple files, or using steganography techniques can provide some level of evasion, they do not offer the same effectiveness in terms of reducing visibility and providing security as the compression and encryption combination does. These alternatives might still be identified by security tools or analyzed by skilled defenders, making them less reliable for stealth operations.