On the Security of Some Self-Healing Key Distribution Schemes

Self-healing key distribution schemes are particularly useful when there is no network infrastructure or such infrastructure has been destroyed. A self-healing mechanism can allow group users to recover lost session keys and is therefore quite suitable establishing group keys over an unreliable network where broadcast messages loss may occur frequently. Many self-healing key distribution schemes are proposed. Through security analysis,we found that three schemes are insecure.The three insecure self-healing key distribution schemes come from three different papers. We designed the corresponding attack methods.Our attack methods showed that the revoked users (or any users) can also get the session key. It violates the important security requirement of self-healing key distribution.