The window washers were stuck after a cable snapped on the motorized scaffold as it was being raised back to the roof just before 1 p.m.
Emergency workers secured the scaffolding, which was hanging at a roughly 65 degree angle at approximately the 68th floor.
Rescue workers had to break and remove two layers of glass to reach the workers, because the windows do not open. Crews were also lowering a second scaffold from the roof, but it was raised back up after it became clear that the window could be breached. A third option would have involved a firefighter rappelling down the side of the building.
"They're safe," a Port Authority official told ABC News. "The Fire Department is doing what the Fire Department does. They're talking to them."
People on the ground were moved back in case glass began flying, and the 9/11 Memorial was evacuated and closed as a precaution.
The workers, employed by a company contracted by the building's manager, were secured by their safety harnesses.
Footage showed ropes being dropped to the scaffolding, as well.