[java] Java SecurityException: signer information does not match

I recompiled my classes as usual, and suddenly got the following error message. Why? How can I fix it?

java.lang.SecurityException: class "Chinese_English_Dictionary"'s signer information does not match signer information of other classes in the same package
    at java.lang.ClassLoader.checkCerts(ClassLoader.java:776)

this happened to me when using JUnit + rest assured + hamcrest, in this case, dont add junit to build path, if you have the maven project, this resolved me, below is the pom.xml

<dependencies>

    <dependency>
        <groupId>io.rest-assured</groupId>
        <artifactId>rest-assured</artifactId>
        <version>3.0.0</version>
    </dependency>

    <dependency>
        <groupId>org.hamcrest</groupId>
        <artifactId>hamcrest-all</artifactId>
        <version>1.3</version>
    </dependency>


    <!-- https://mvnrepository.com/artifact/junit/junit -->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>

    </dependency>


</dependencies>

A bit too old thread but since I was stuck for quite some time on this, here's the fix (hope it helps someone)

My scenario:

The package name is : com.abc.def. There are 2 jar files which contain classes from this package say jar1 and jar2 i.e. some classes are present in jar1 and others in jar2. These jar files are signed using the same keystore but at different times in the build (i.e. separately). That seems to result into different signature for the files in jar1 and jar2.

I put all the files in jar1 and built (and signed) them all together. The problem goes away.

PS: The package names and jar file names are only examples

This can occur with the cglib-instrumented proxies because CGLIB uses his own signer information instead of the signer information of the application target class.

If you added all the jars from bouncycastle.org (in my case from crypto-159.zip), just remove the ones for the JDKs that do not apply to you. There are redundancies. You probably only need the "jdk15on" jars.

In my case it was a package name conflict. Current project and signed referenced library had one package in common package.foo.utils. Just changed the current project error-prone package name to something else.

I was running JUNIT 5 and was also referencing Hamcrest external jar. But Hamcrest is also part of JUNIT 5 library. So, I have to change the order of external Hamecrest jar file up the JUNIT 5 library in build path.

This also happens if you include one file with different names or from different locations twice, especially if these are two different versions of the same file.

This question has lasted for a long time but I want to pitch in something. I have been working on a Spring project challenge and I discovered that in Eclipse IDE. If you are using Maven or Gradle for Spring Boot Rest APIs, you have to remove the Junit 4 or 5 in the build path and include Junit in your pom.xml or Gradle build file. I guess that applies to yml configuration file too.

If you're running it in Eclipse, check the jars of any projects added to the build path; or do control-shift-T and scan for multiple jars matching the same namespace. Then remove redundant or outdated jars from the project's build path.

I had a similar exception:

java.lang.SecurityException: class "org.hamcrest.Matchers"'s signer information does not match signer information of other classes in the same package

The root problem was that I included the Hamcrest library twice. Once using Maven pom file. And I also added the JUnit 4 library (which also contains a Hamcrest library) to the project's build path. I simply had to remove JUnit from the build path and everything was fine.

I could fix it.

Root Cause: This is a common issue when using the Sun JAXB implementation with signed jars. Essentially the JAXB implementation is trying to avoid reflection by generating a class to directly access the properties without using reflection. Unfortunately, it generates this new class in the same package as the class being accessed which is where this error comes from.

Resolution: Add the following system property to disable the JAXB optimizations that are not compatible with signed jars: -Dcom.sun.xml.bind.v2.bytecode.ClassTailor.noOptimize=true

Ref: https://access.redhat.com/site/solutions/42149

Based on @Mohit Phougat response, if you are running a Groovy with @Grab annotations, you could try to re-order such annotations.

1. After sign, access: dist\lib
2. Find extra .jar
3. Using Winrar, You extract for a folder (extract to "folder name") option
4. Access: META-INF/MANIFEST.MF
5. Delete each signature like that:

Name: net/sf/jasperreports/engine/util/xml/JaxenXPathExecuterFactory.c lass SHA-256-Digest: q3B5wW+hLX/+lP2+L0/6wRVXRHq1mISBo1dkixT6Vxc=

1. Save the file
2. Zip again
3. Renaime ext to .jar back
4. Already

I am having this problem with Eclipse and JUnit 5. My solution is inspired by the previous answer by user2066936 It is to reconfig the ordering of the import libraries:

1. Right click the project.
2. Open [Java Build Path].
3. Click Order and Export.
4. Then push JUNIT to upper priority.

In my case, I had duplicated JAR version of BouncyCastle in my library path :S

A. If you use maven, an useful way to debug clashing jars is:

mvn dependency:tree

For example, for an exception:

java.lang.SecurityException: class "javax.servlet.HttpConstraintElement"'s signer information does not match signer information of other classes in the same package

we do:

mvn dependency:tree|grep servlet

Its output:

[INFO] +- javax.servlet:servlet-api:jar:2.5:compile
[INFO] +- javax.servlet:jstl:jar:1.2:compile
[INFO] |  +- org.eclipse.jetty.orbit:javax.servlet.jsp:jar:2.2.0.v201112011158:compile
[INFO] |  +- org.eclipse.jetty.orbit:javax.servlet.jsp.jstl:jar:1.2.0.v201105211821:compile
[INFO] |  +- org.eclipse.jetty.orbit:javax.servlet:jar:3.0.0.v201112011016:compile
[INFO] +- org.eclipse.jetty:jetty-servlet:jar:9.0.0.RC2:compile

shows clashing servlet-api 2.5 and javax.servlet 3.0.0.x.

B. Other useful hints (how to debug the security exception and how to exclude maven deps) are at the question at Signer information does not match.

A simple way around it is just try changing the order of your imported jar files which can be done from (Eclipse). Right click on your package -> Build Path -> Configure build path -> References and Libraries -> Order and Export. Try changing the order of jars which contain signature files.