ESET NOD32 is a commercial antivirus product. Downloading updates or licensed versions from unofficial sources (including university portals without proper authorization) is piracy , which violates software copyright laws and the university's IT policies. The University of Villa Clara may offer licensed ESET software only to its students and staff through an internal portal—but that access is restricted to their network and credentials. Any public "free download" outside that system is likely illegal or malicious.
I understand you're looking for information about downloading NOD32 updates for free, specifically for the University of Villa Clara. However, I must clarify some important points before providing a helpful response. ESET NOD32 is a commercial antivirus product
Remember: A free antivirus you update legally is better than a premium one you update illegally. Any public "free download" outside that system is