Iranian Society of Cryptology The ISC International Journal of Information Security 2008-2045 12 2 2020 07 01 Enhanced Flush+Reload Attack on AES 81 89 110645 10.22042/isecure.2020.219248.519 EN Milad Seddigh Cyberspace Research Institute, Shahid Beheshti University, Iran Hadi Soleimany Iran-Tehran Journal Article 2020 02 09 In cloud computing, multiple users can share the same physical machine that can potentially leak secret information, in particular when the memory de-duplication is enabled. Flush+Reload attack is a cache-based attack that makes use of resource sharing. T-table implementation of AES is commonly used in the crypto libraries like OpenSSL. <br /> Several Flush+Reload attacks on T-table implementation of AES have been proposed in the literature which requires a notable number of encryptions. In this paper, we present a technique to enhance the Flush+Reload attack on AES in the ciphertext-only scenario by significantly reducing the number of needed encryptions in both native and cross-VM setups. In this paper, we focus on finding the wrong key candidates and keep the right key by considering only the cache miss event. Our attack is faster than previous Flush+Reload attacks. In particular, our method can speed-up the Flush+Reload attack in cross-VM environment significantly. To verify the theoretical model, we implemented the proposed attack. https://www.isecure-journal.com/article_110645_e37bfa9ce9e952f29fd0b62410412ddd.pdf