ON THE (IN)SECURITY OF TWO BUYER-SELLER WATERMARKING PROTOCOLS
Geong Sen Poh, Keith M. Martin · 2008
A buyer-seller watermarking protocol deters dishonest buyers from illegally distributing bought content. This is achieved by giving the seller the capability to trace and identify these buyers, while also allowing the seller to prove illegal acts to a third party. At the same time, an honest buyer is prevented from being falsely accused of illegal content distribution by the seller. Many protocols have been proposed, with two recent proposals being the protocols proposed by Ibrahim et al. in IAS 2007 and SECRYPT 2007. We will show that these protocols are not secure, especially for the seller. We further put forward our thoughts on how it is possible to avoid the security weaknesses found in them.