A Third is All You Need: Extended Partial Key Exposure Attack on CRT-RSA with Additive Exponent Blinding

ePrint Report: A Third is All You Need: Extended Partial Key Exposure Attack on CRT-RSA with Additive Exponent Blinding

Yuanyuan Zhou, Joop van de Pol, Yu Yu, François-Xavier Standaert

At Eurocrypt 2022, May et al. proposed a partial key exposure (PKE) attack on CRT-RSA that efficiently factors $N$ knowing only a $\frac{1}{3}$-fraction of either most significant bits (MSBs) or least significant bits (LSBs) of private exponents $d_p$ and $d_q$ for public exponent $e \approx N^{\frac{1}{12}}$. In practice, PKE attacks typically …

attack crt eprint report key rsa third