Hybrid attacks on sparse LWE

In this talk, I will present hybrid primal attack on Learning With Errors with sparse secret. For this, I introduce Batch Closest Vector Problem and how to solve it with state-of-the-art methods. These include efficient guessing algorithm, and Randomized Slicer Algorithm for Batch CVP. I will also speak about practical aspects of the hybrid attack. The talk is based in the joing work with Alexander Karenin, Alexander May, Julian Nowakowski “ Fast Slicer for Batch-CVP: Making Lattice Hybrid Attacks Practical” (AsiaCrypt 2025).