Backupify, a Cambridge-based provider of online backup services for cloud application data, announced Wednesday that it has secured $9 million in Series C funding.

The funding is from Symantec Corp. as well as existing investors Avalon Ventures, General Catalyst Partners, and Lowercase Capital, said Backupify, which added that it has now raised a total of $19.5 million.

‘‘As more data is stored in cloud-based services, the threats to that data posed by user error, corruption and hacking also increase. Maintaining a secure second copy of cloud-based data can mitigate each of these risks,’’ Anthony Woolf, Symantec’s senior director of corporate development, said in a statement. ‘‘We support Backupify’s efforts to help consumers and businesses protect the data they create in cloud applications.’’