WEAKNESSES IN SOME RECENT KEY AGREEMENT PROTOCOLS

B. Arazi recently proposed a way to integrate the DSS (digital signatu re standard) to the Diffie-Hellman key exchange system to obtain an au thenticated key establishment mechanism for secret session keys. This Letter poins out the following weakness in the Arazi system: if one ke y is compromised then the others will be disclosed as well. A similar weakness appears also in another recently presented key distribution s ystem.