1. The US authorities have banned the use of Kaspersky antivirus software nationwide, extending the prohibition beyond government devices to all businesses and consumers. 2. The ban, effective from July 20 for sales and September 29 for updates, is based on security concerns that the software could enable Russian cyberattacks and influence US governance. 3. Kaspersky has responded by announcing legal actions to protect its business, asserting that the decision was based on geopolitical climate rather than thorough software analysis.