中文摘要：

针对文献[4]提出的一种新的在标准模型下可证安全的数字签名方案（简记为NPSDS方案），分析了该方案建立的数学基础——“极微本原”的DRRSA问题困难性假设存在的矛盾，指出NPSDS方案的安全性证明过程中存在的逻辑错误。由于文献[4]中方案的签名验证过程过于简单，可利用DRRSA问题伪造有效签名。

英文摘要：

In literature [4], a new provably secure digital signature （NPSDS） scheme in standard model is given. The hardness assumption of DRRSA problem lies in the mathematical foundation and atomic primitive of the NPSDS scheme. However, the DRRSA problem is proven contradictive, and logic errors are found in its security proof. Moreover, valid signatures can be forged by using the DRRSA problem, since its signature verification is excessively simple.