Today, Microsoft released a new version of their Enhanced Mitigation Experience Toolkit. A rather unwieldy name, but quite interesting technology - with EMET, legacy applications on OS versions as far back as WindowsXP can now also be protected with Data Execution Prevention (DEP), Exception Handler Overwrite Protection (SEHOP) and more, and the application doesn't even have to be DEP-aware. If you have vulnerable legacy apps on Windows that you need to keep alive for a little while longer, I suggest to take a look at EMETv2.
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