Looks like that firefox on mac incorrectly compares update number, and shows message that plugin is vulnerable and should be updated for updates releases that contains 3 digits.
There is no issue on windows and linux.

Product(s) tested: jdk7u101
OS/architecture: mac os x 10.10/10.11
Reproducible: Always
Is it a Regression: Not sure
Regression introduced in release/build: 7u101 nightly
Test result on the last GAed release for this train: Pass
Is it a platform specific issue: Yes
[If platform specific issue] Is it a new (previously unsupported) OS/browser/mode testing: No
OS/browser version: mac os x 10.11 / 10.10 + firefox
Steps to reproduce:
1) install jdk7u101
2) open java version applet in firefox: http://www.java.com/en/download/installed8.jsp

actual result: see screenshot