NATO and Afghan troops have repelled twin pre-dawn attacks on two bases in eastern Afghanistan.
Air support was called in after the Chapman and Salerno bases belonging to the US came under assault in the early hours.
24 militants were killed – some of them were found to be wearing suicide vests.
There were no ISAF casualties in the attacks, which happened in Khost province near the border with Pakistan.
Meanwhile, the Afghan President has dismissed reports that the CIA was paying one of his advisers for inside information.
Hamid Karzai says it is an insult aimed at discrediting his government.
The US fears corruption is boosting the Taliban-led insurgency and complicating efforts to strengthen central government control so that foreign troops can begin withdrawing in July 2011.