by , 9:40 AM EST, November 21st, 2007

Heise Security says Apple's Mail application in Mac OS X 10.5 may include a security flaw that the company previously patched in Mac OS X 10.4. The flaw could allow an attacker to trick Mail users into running an application by disguising it as a JPEG email attachment.

Apple patched the flaw in Tiger's Mail application in March 2006, but somehow it seems the same security hole was reintroduced when Leopard shipped at the end of October.

The security company has developed a demonstration showing the flaw. The demonstration emails a harmless attachment that launches the Terminal application and displays the contents of the current directory.

This potential security flaw appears to impact Leopard users only. Tiger users with current updates installed are not impacted.