FULL PRODUCT VERSION :
java version "1.8.0_40"
Java(TM) SE Runtime Environment (build 1.8.0_40-b25)
Java HotSpot(TM) 64-Bit Server VM (build 25.40-b25, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
Bug JDK-8029354 reproduces with underscore in hostname. I have to use third paty library access webService by intranet URL with underscore in hostname in thrid level domain. Hostname is also used to validate server, so I cannot use ip addres as workaround.

Caused by: java.lang.IllegalArgumentException: Invalid characters in hostname
                at java.net.HostPortrange.toLowerCase(HostPortrange.java:189)
                at java.net.HostPortrange.<init>(HostPortrange.java:150)
                at java.net.URLPermission$Authority.<init>(URLPermission.java:481)
                at java.net.URLPermission.parseURI(URLPermission.java:449)
                at java.net.URLPermission.init(URLPermission.java:170)
                at java.net.URLPermission.<init>(URLPermission.java:166)
                at sun.net.www.protocol.http.HttpURLConnection.URLtoSocketPermission(HttpURLConnection.java:1032)
                at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1425)
                at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(HttpURLConnection.java:2978)
                at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:489)


REGRESSION. Last worked in version 7u80

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Try to access any URL with uderscore in hostname

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
access URL with uderscore in hostname without exception
ACTUAL -
Caused by: java.lang.IllegalArgumentException: Invalid characters in hostname
                at java.net.HostPortrange.toLowerCase(HostPortrange.java:189)
                at java.net.HostPortrange.<init>(HostPortrange.java:150)
                at java.net.URLPermission$Authority.<init>(URLPermission.java:481)
                at java.net.URLPermission.parseURI(URLPermission.java:449)
                at java.net.URLPermission.init(URLPermission.java:170)
                at java.net.URLPermission.<init>(URLPermission.java:166)
                at sun.net.www.protocol.http.HttpURLConnection.URLtoSocketPermission(HttpURLConnection.java:1032)
                at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1425)
                at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(HttpURLConnection.java:2978)
                at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:489)


ERROR MESSAGES/STACK TRACES THAT OCCUR :
Caused by: java.lang.IllegalArgumentException: Invalid characters in hostname
                at java.net.HostPortrange.toLowerCase(HostPortrange.java:189)
                at java.net.HostPortrange.<init>(HostPortrange.java:150)
                at java.net.URLPermission$Authority.<init>(URLPermission.java:481)
                at java.net.URLPermission.parseURI(URLPermission.java:449)
                at java.net.URLPermission.init(URLPermission.java:170)
                at java.net.URLPermission.<init>(URLPermission.java:166)
                at sun.net.www.protocol.http.HttpURLConnection.URLtoSocketPermission(HttpURLConnection.java:1032)
                at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1425)
                at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(HttpURLConnection.java:2978)
                at java.net.HttpURLConnection.getResponseCode(HttpURLConnection.java:489)


REPRODUCIBILITY :
This bug can be reproduced always.