I was also facing the same problem while reading pdf uing itext 5.5.10.
I changed the dependancies to following :
<dependency><groupId>com.itextpdf</groupId><artifactId>itextpdf</artifactId><version>5.5.4</version></dependency><dependency><groupId>org.bouncycastle</groupId><artifactId>bcprov-jdk15on</artifactId><version>1.49</version></dependency><dependency><groupId>org.bouncycastle</groupId><artifactId>bcpkix-jdk15on</artifactId><version>1.49</version></dependency>You can also refer : https://stackoverflow.com/a/27575336/3150912
