The group announced on Tuesday that it had struck Ehud Leviathan Engineering, David Engineers, and H.G.M. Engineering, without making any demands for money or anything else.
It also leaked data from the Israeli firms, including projects, maps, contracts, pictures, letters and video conferencing images.
Documents about infrastructure projects such as highways and public water systems, as well as a tender concerning construction at the entrance of al-Quds were also among the leaked information.
Moses Staff said that the information it had exposed did not include everything that it had obtained, and that it would gradually release the rest.
Recently, Black Shadow group hackers broke into the servers of Israeli internet hosting company Cyberserve, bringing down a number of widely-used websites and warning the firm that it was in possession of data that could be leaked.
It further demanded a ransom payment of $1 million in digital currency to stop the leak.
Separately, Moses Staff said it had access to confidential documents, including reports, operational maps, information about soldiers and units, and letters and correspondence.
In an earlier attack, it leaked photos of Israeli minister of military affairs Benny Gantz and army soldiers and a 2010 letter from Gantz to the deputy chief of the joint chiefs of staff and chief of intelligence in the Jordanian Armed Forces.
It also released Excel files containing the names, ID numbers, emails, addresses, phone numbers and even socioeconomic status of Israeli army soldiers, mechina pre-military students and individuals connected to the ministry of military affairs.
“We are going to publish this information to aware [sic] all the world about the Israeli authorities’ crimes,” the hacking group said on its Telegram channel. “We’ve kept an eye on you for many years, at every moment and on each step. All your decisions and statements have been under our surveillance. Eventually, we will strike you while you never would have imagined.”
According to Moses Staff’s website, the group has hacked over 165 servers and 254 websites and compiled over 11 terabytes of data, including Israel Post, the ministry of military affairs, files related to Gantz, the Electron Csillag company and Epsilor company.
The group also noted that it will not forget “the soldiers whose blood is shed due to wrong policies and fruitless wars, the mothers mourning for their children, and all the cruelty and injustice done to the people of this nation,” vowing to “keep fighting! To uncover your hidden crimes.”