Monday, we reported that Saudi Arabian hackers—one under the handle of ox0mar and with the group named Group-xp—hit Israeli financial sector websites and an airline carrier causing both considerable lag but did not take them offline. This came shortly after last week’s publication of 400,000 Israeli credit card numbers (a small percentage of which were active) by Saudi hackers.

It looks like it’s on between the two nations’ hacker communities.

Shortly thereafter, apparent Israeli hacker teams responded with reciprocal force against Saudi Arabian private sector websites in an in-kind cyberwarfare skirmish. The hackers brought down the websites of the Saudi Stock Exchange (Tadawul) and the Abu Dhabi Securities Exchange (ADX.)

The Israeli hackers go by the group-handle of IDF-Team and were able to paralyze the Tadawul website while causing significant delays to the ADX—although there have been reports from the Financial Times that the Tadawul had been slowed to a crawl and ADX suffered massive outages. It will be difficult to know exactly how the two sites managed the DDOS attack until the aftermath is investigated.

According to Haaretz.com, the hackers from ITF-Team called the initial strike from [X] against Israeli financial websites on Monday “pathetic” and waned that if attacks continue they will “move to the next stage and paralyze websites for a period of two weeks to a month.”

Early Tuesday, a pro-Israel hacker going under the handle Hannibal published 30,000 e-mail addresses and Facebook passwords that he claims belong to “helpless Arabs.” He wrote that this leak of passwords and e-mail addresses came in retaliation to Friday’s publication of Israeli credit cards.

“I noticed that poor intelligence of 0x omar and his friends [sic],” they wrote on pastebin.com. “State of Israel, not to worry, you’re in the hands of the world’s best hacker that I am [sic],” Hannibal continued. “I will continue to support the government of Israel will continue to attack the Arab countries.”

Not to be left out @anonymouSabu chimed in, “Anti-Israeli hacks exploding,” he writes. “I’m glad the paki hack scene coming back. missed it.” Although “paki” is commonly short for Pakistani in this context, but all involved seem to think that it’s Saudi Arabian nationalist hackers who are behind the attacks on Israel.

The AnonymouSabu Twitter account is best known for its connection to Anonymous and for being part of reporting the Christmas hack and leak of information from security think tank Stratfor. It’s hard to say what this account has to do with skirmish between Israel and Saudi Arabia; but hackers are a status-centric breed and like to pat each other on the back publicly if they can. So we can expect to see AnonymouSabu to speak more often about the groups involved even if the account owner doesn’t know them personally.