Description
Apache Standard Taglibs before 1.2.3 allows remote attackers to execute arbitrary code or conduct external XML entity (XXE) attacks via a crafted XSLT extension in a (1) <x:parse> or (2) <x:transform> JSTL XML tag.
Mitigation
We recommend upgrading to a version of this component that is not vulnerable to this specific issue.
Note for the fixed version(s):
```
This version uses JAXP's FEATURE_SECURE_PROCESSING to restrict XML processing. Depending on the Java runtime version in use, additional configuration may be required:
Java8: External entity access is automatically disabled if a SecurityManager is active.
Java7: JAXP properties may need to be used to disable external access. See http://docs.oracle.com/javase/tutorial/jaxp/properties/properties.html
Java6 and earlier: A new system property org.apache.taglibs.standard.xml.accessExternalEntity
may be used to specify the protocols that can be used to access external entities. This defaults
to "all" if no SecurityManager is present and to "" (thereby disabling access) if
a SecurityManager is detected.
```
Reference: [http://mail-archives.apache.org/mod_mbox/tomcat-taglibs-user/201502.mbox/%3C82207A16-6348-4DEE-877E-F7B87292576A%40apache.org%3E](http://mail-archives.apache.org/mod_mbox/tomcat-taglibs-user/201502.mbox/%3C82207A16-6348-4DEE-877E-F7B87292576A%40apache.org%3E)
