I gather the Italians stole the US codes and picked up details:
"Both sides brought up all the troops they had. Slowly but surely the British drew a ring around the Axis divisions. Nevertheless, despite all tactical successes, the onslaught of the British did not achieve decisive results. Wherever the British started an action, Rommel immediately sent forces to oppose them. He even sent a column behind the British in the direction of Halfaya and cut their line of supply. He always did the right thing at the right time.
Small wonder, for Garrulus was sending one telegram after another to Washington. He ranged all over the battle area, saw and heard everything, knew all preparations, every intention, every movement of the British forces, and he transmitted it all to the United States. The German intercept station copied each message and sent it promptly by teletype to Berlin, where it was deciphered and forwarded by the speediest possible means to Rommel. The whole thing took only a few hours. By now the cryptosystem had been completely solved.
The British were much surprised. Preparations for the offensive had been so thorough that destruction of the Axis troops in its very first phase had been considered certain. Something had not clicked. General Auchinleck, Commander in Chief in the Near East and Wavell's successor, flew from Cairo to Cunningham's headquarters and on 26 November relieved him of his post. A young general of 44 years, Ritchie, was appointed commander of the British Eighth Army. On 8 December Rommel pushed through a weak point in the British encirclement, disengaging his troops without being detected. Before the British recovered from their surprise he had escaped to the westward. On 11 December Churchill stated in the House of Commons that the Libyan campaign had not gone as expected."