Image authentication must be able to verify the origin and the integrity of digital images, and some research has made efforts in that. In this paper, we reveal a new type of malicious alteration which we call the “Tattooing Attack”. It can successfully alter the protected image if the collision of the authentication bits corresponding to the altered image and the original watermarking image can be found. To make our point, we chose Chang et al.'s image authentication scheme based on watermarking techniques for tampering detection as an example. The authors will analyze the reasons why the attack is successful, and then they delineate the conditions making the attack possible. Since the result can be generally applied into other schemes, the authors evaluate such schemes to examine the soundness of these conditions. Finally, a solution is provided for all tamper detection schemes suffering from the Tattooing Attack.
Passive Copy-Move Tamper Detection Methods for Digital Images