So to be clear, do you think this must be untrue?
Hacker group Anonymous gives "Israel" a 48-hour ultimatum to stop its war on Gaza, or else it will publish confidential information and sensitive files in its possession of the Security Ministry.
This, and the hope it might be effective on bringing about a ceasefire, was the reason for the OP, not any question about whether or not Hamas launched a justified revolt against colonialism.
Reuters reported on Anonymous making a similar threat last April, so I don’t think Al-Maydeen is necessarily not to be believed.
A group called Anonymous for Justice claimed responsibility for the breach, which it said included the retrieval of nearly 300 gigabytes of data. On its website, the group said it would continue attacking Israel "until the war in Gaza stops". (Excerpt from:)
www.reuters.com/world/middle-east/israels-justice-ministry-reviewing-cyber-incident-after-hacktivists-claim-breach-2024-04-05/