A loosely organized group of Internet hacktivists took down Visa's website Wednesday, after organizing a similar attack on MasterCard. A loosely organized group of Internet hacktivists took down Visa’s website Wednesday, after organizing a similar attack on MasterCard.The group, called Anonymous, has been encouraging volunteers to download software called LOIC (Low Orbit Ion Cannon), which lets them centrally control these systems and direct them into a distributed denial of service attack (DDoS). The point of the attacks is to put pressure on financial companies that recently cut ties with the WikiLeaks website over its planned publication of more than a quarter million U.S. Department of State classified cables.After successfully knocking Mastercard.com offline, the group decided to attack Visa.com around 1 p.m. Pacific time. The site was quickly knocked offline.“IT’S DOWN! KEEP FIRING!!!” the group said in a Twitter message a few minutes later. The Mastercard website went offline when about 400 computers targeted the LOIC software at it. By the time Visa was hit, however, there were more than 2,000 people using the software, according to Paul Mutton, a security analyst with Netcraft. Visa was a much harder target to take down, because unlike Mastercard.com, it was distributed over the Akamai Technologies network. This meant that more Visa-hosting computers had to be overwhelmed to finally knock the site offline.Reached shortly after 1 p.m. Pacific time, a Visa representative was unable to immediately comment on the attack. WikiLeaks supporters have hit the sites of other companies that have cut ties with WikiLeaks, including payment processor PostFinance, PayPal and EveryDNS.Robert McMillan covers computer security and general technology breaking news for The IDG News Service. Follow Robert on Twitter at @bobmcmillan. Robert’s e-mail address is robert_mcmillan@idg.com Related content news Conti-linked ransomware takes in $107 million in ransoms: Report A ransomware campaign linked to the ostensibly defunct Conti malware group has targeted mostly US businesses, in a costly series of attacks. By Jon Gold Nov 30, 2023 3 mins Ransomware Malware Cybercrime news Okta confirms recent hack affected all customers within the affected system Contrary to its earlier analysis, Okta has confirmed that all of its customer support system users are affected by the recent security incident. By Shweta Sharma Nov 30, 2023 3 mins Data Breach news Top cybersecurity product news of the week New product and service announcements from Wiz, Palo Alto Networks, Sophos, SecureAuth, Kasada, Lacework, Cycode, and more. By CSO staff Nov 30, 2023 17 mins Generative AI Security feature How to maintain a solid cybersecurity posture during a natural disaster Fire, flood, eathquake, hurricane, tornado: natural disasters are becoming more prevalent and they’re a threat to cybersecurity that isn’t always on a company’s radar. Here are some ways to prepare for the worst. By James Careless Nov 30, 2023 8 mins Security Operations Center Data and Information Security Security Practices Podcasts Videos Resources Events SUBSCRIBE TO OUR NEWSLETTER From our editors straight to your inbox Get started by entering your email address below. Please enter a valid email address Subscribe