jakarta-taglibs-standard is the Java Standard Tag Library . This library is used in conjunction with Tomcat and Java Server Pages . It was found that the Java Standard Tag Library allowed the processing of untrusted XML documents to utilize external entity references, which could access resources on the host system and, potentially, allowing arbitrary code execution. Note: jakarta-taglibs-standard users may need to take additional steps after applying this update. Detailed instructions on the additional steps can be found here: https://access.redhat.com/solutions/1584363 All jakarta-taglibs-standard users are advised to upgrade to these updated packages, which contain a backported patch to correct this issue.