# Remember once Tomcat upgrade - ghost cat

I. Background

Recently Tomcat was broke ghost cat vulnerabilities, covering all versions from 6-9 in the move, so do the current upgrade is the means, then it is about how SpringBoot built-in Tomcat upgrade.

Second, upgrade

1 download the corresponding version

Tomcat official website to download

Here are three versions of 7,8,9, 10 is a test version, or for the pursuit of stability in all three versions which choose it. Less than 7 to be automatically upgraded, you may also need to modify the code.

Here I chose the 9.0.31

1. You can download EMbedded
2. unzip
   
3. Where .m2 open maven repository folder directory
4. Find the tomcat folder, create a new directory and 9.0.31 core, el, websock three subdirectories, the compressed bag three corresponding jar package with this character into the folder below
5. Open eclipse or inside the IDEA project to find your POM file
6. in The following new attributes <tomcat.version> 9.0.31 </tomcat.version>
7. At this time in the IDEA Maven do not forget to be Reimport.
8. Start the project, you will see your apache / tomcat becomes 9.0.31