The phrase "external attacker" refers to an individual or a group who tries to harm or exploit a computer network or system from outside. They are not part of the organization or system they are targeting. Full definition
However, security software company Symantec says individual voters are not at any real risk, and it has not seen a single incident of external attackers interfering with voters. (bbc.com)
The first is because an external attacker can compromise workers» identities, hacking and impersonating them and using their credentials to run amok. (fortune.com)
On Tuesday, Tether announced that an «external attacker» had taken $ 30 million worth of Tether from the company's online wallets. (thestar.com)