I'm not even sure that Hadoop's combination of the relevant dependencies is vulnerable (even if they are, this is a relatively minor vulnerability), but this is at least showing up as an issue in automated vulnerability scans. Details can be found here https://maven.apache.org/security.html (CVE-2013-0253, CVE-2012-6153). Essentially the combination of maven 3.0.4 (we use 3.0, and I guess that maps to 3.0.4?) and older versions of wagon plugin don't use SSL properly (note that we neither use the WebDAV provider nor a 2.x version of the SSH plugin, which is why I suspect that the vulnerability does not affect Hadoop).
I know some dependencies can be especially troublesome to upgrade - I suspect that Maven's critical role in our build might make this risky - so if anyone has ideas for how to more completely test this than a full build, please chime in,