Hackers operating under the "Nightmare Group" banner managed to shut down the websites of both the Tel Aviv Stock Exchange (TASE) and El Al (Israel Airlines) on Monday.
However, internal systems appeared unaffected by the digital infiltrators, as stock trading and flights operated normally despite the cyber attack.
"There has been an attack by hackers on the access routes to the (TASE) website," Orna Goren, deputy manager of the exchange's marketing and communications unit told Reuters. "The stock exchange's trading activities are operating normally."
The attack prompted Israel Bank to block IP addresses originating from Saudi Arabia, Iran and Algeria in an effort to thwart further security breaches.
The latest hack attacks come just weeks after Saudi hacker 0xOmar and the "Nightmare Group" compromised the credit cards of millions of Israelis - an operation that was subsequently endorsed by Hamas.
"The penetration into Israeli websites opens a new front for electronic resistance and war against the Israeli occupation,” Hamas spokesperson Sami Abu Zuhri on Sunday.
As TG Daily previously reported, the growing specter of cyber warfare has prompted the Israel Defense Forces (IDF) to step up its recruit of hackers who will be tasked with securing the country's digital perimeter.
"We are not where we would like to be when it comes to the cyber world and we are working to improve our capabilities," a senior IDF officer recently acknowledged. "[And] these [men and women] are some of the top experts in their field."
The new recruits are slated to serve in Unit 8200 under the auspices of Military Intelligence, as well as in the C4I (Cyber) Directorate, where they will help defend military, government and civilian networks.