NSIS Installer Identification

I've scrounged around the internet trying to find a solution to this problem without much luck. I want to be able to identify whether an uninstaller is compiled using NSIS. A perfect example is Firefox. Is there a common offset associated with NSIS uninstallers that identifies the file as being a NSIS compiled exe?

If you have a look at the code in Source\exehead\fileform.c (lines 196 to 219), there is a magic code that the installer\uninstaller looks for when it's run.

Use Resource Hacker. A standard NSIS file will probably say something about Nullsoft or NSIS.ExeHead in the manifest. You could also look at the dialog resources. Compare them with a known NSIS installer and it should be easy to spot if they match.

But as Jason says, looking for the magic data with a hex editor is the most reliable way.

7-Zip might also be able to tell you by looking at the archive properties.