"Software vendors regularly make announcements that certain versions of software will no longer be supported after a particular date. Such dates are known as End-of-Life. After the End-of-Life, software is no longer supported and can therefore not be considered to be secure. The NCSC advises to update systems after the announcement as soon as possible.
Software that is still being used after its End-of-Life will become increasingly vulnerable to attacks. When an End-of-Life announcement is made, you should start with the upgrade process as soon as possible. Upgrading may lead to compatibility problems with other programs. Therefore you should start to plan, test and implement upgrades as soon as possible.
Some systems, such as medical or industrial machinery, cannot be upgraded: alternative measures exist for these, but they require intensive administration."
The factsheet is available at https://www.ncsc.nl/english/services/expertise-advice/knowledge-sharing/factsheets/software-has-an-expiry-date.html.
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