New SEC regulations require companies to disclose a breach within 4 days of determining a breach is material. Such disclosers are made to the SEC in 8-K and 8-K/A (Amendment) files.
Several users have asked for notifications when companies disclose material incidents to the SEC. Precize has developed a bot that monitors the SEC Edgar site hourly and sends email alerts with the link to any new 8-K filings.
Here are the recent Cyber Security 8-K filings done by Public companies with the SEC in descending order (most recent on top)