We describe an attack on the RSA cryptosystem when the private exponent
is chosen to be ’small’, under the condition that a sufficient amount of bits of
is available to the attacker. The attack uses a 2-dimensional lattice and is therefore (in the area of the keyspace where it applies) more efficient than known attacks using Coppersmith techniques. Moreover, we show that the attacks of Wiener and Verheul/Van Tilborg, using continued fractions techniques, are special deterministic cases of our attack, which in general is heuristic.