A rogue access point is the most likely attack method because the administrator accessed company systems from an airport, which is a common location for malicious or fake wireless networks. An attacker can set up an evil twin or rogue access point that appears legitimate, tricking users into connecting. Once connected, the attacker may intercept traffic, capture credentials, or perform man-in-the-middle activity. The later unauthorized configuration changes indicate the attacker likely obtained or abused the administrator’s session or credentials. Shoulder surfing would require visually observing the credentials, which is possible but less directly supported. Skimming usually targets payment card data. A keylogger requires malware installed on the administrator’s device, which is not indicated. The airport network clue strongly supports rogue access point.

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