Several recently proposed code-based cryptosystems base their security on a slightly generalized version of the classical (syndrome) decoding problem. Namely, in the so-called restricted (syndrome) decoding problem, the error values stem from a restricted set. In this paper, we propose new generic decoders, that are inspired by subset sum solvers and tailored to the new setting. The introduced algorithms take the restricted structure of the error set into account in order to utilize the representation technique efficiently. This leads to a considerable decrease in the security levels of recently published code-based cryptosystems.

翻译：最近提出的几种基于编码的密码系统将其安全性建立在经典（综合征）解码问题的略微广义版本之上。具体而言，在所谓的受限（综合征）解码问题中，错误值源自一个受限集合。本文提出了受子集和求解器启发并针对新场景定制的新型通用解码器。所引入的算法通过利用误差集合的受限结构，高效运用表示技术，从而显著降低了近期发表的基于编码的密码系统的安全等级。