Mozilla Firefox, a free open-source browser, has steadily gained users since its introduction in 2004 with features such as an integrated search window to allow users to do a Web query without opening another page, tab browsing to toggle between different sites and a pop-up window blocker.
These features are included in the new Internet Explorer and Microsoft also touted the security improvements to the browser including color-coded warnings in the address bar to indicate whether a Web site can be trusted.
IE 7 is available immediately to Windows XP users and it will eventually serve as the default browser for Microsoft's much-anticipated Windows Vista operating system, due out to consumers in early 2007.
According to analysts, consumers increasingly identify the quality of an operating system with the quality of its browser and that makes a well-received browser important for Microsoft -- even if it is not sold as a separate product.
Microsoft said it is already at work on the next version of Internet Explorer to ensure that long gaps between updates do not occur again.
"Should we have done more, sooner, earlier? It's rare to not say that in hindsight," said Dean Hachamovitch, general manager of the Internet Explorer team at Microsoft.
Internet Explorer registered an 86 percent global share in October, Mozilla Firefox 11.5 percent and both Apple Computer Inc.'s Safari and Norway's Opera Software , less than 2 percent, according to OneStat.com.
"It's exciting to see Microsoft reenter the browser space after leaving for five years," said Christopher Beard, vice president of products for Mozilla. "It's great to see that IE is adopting the features that we popularized."
Mozilla said it also plans to release an upgraded browser, Firefox 2, within the next few weeks.
The upgrade will include a feature to allow users to restore work done online if the browser or PC crashes, a spell check function for e-mails or blog postings and suggestions for search queries.
Microsoft's Windows Live is the default search engine on Internet Explorer 7, but users will have the option to change to competing search engines. In Mozilla Firefox, the default search engine in the U.S. is Google Inc.
Competitors raised objections to Microsoft making its own search engine the default setting over concern that it would unfairly drive traffic to Windows Live, but analysts said consumers will eventually gravitate toward the search engine that produces the best results.
The new browser will be sent as an automatic security update and then users will have an option to install the new Internet Explorer onto their PC. Companies also have the option to block its workers from installing the new browser.
IE 7 is available for download at www.microsoft.com/ie.
Less than 24 hours after the launch of Internet Explorer 7, security researchers are poking holes in the new browser. Danish security company Secunia ApS reported Thursday that IE7 contains an information disclosure vulnerability, the same one it reported in IE6 in April. The vulnerability affects the final version of IE7 running on Windows XP with Service Pack 2.
If a surfer uses IE7 to visit a maliciously crafted Web site, that site could exploit the security flaw to read information from a separate, secure site to which the surfer is logged in. That could enable an attacker to read banking details, or messages from a Web-mail account, said Thomas Kristensen, Secunia's chief technology officer. "A phishing attack would be a good place to exploit this," he said.
One of the security features Microsoft Corp. touts for the new browser is the protection it offers users from phishing attacks. Secunia rates the security flaw as "less critical," its second-lowest rating, and suggests disabling active scripting support to protect the computer. The flaw could result in the exposure of sensitive information and can be exploited by a remote system, Secunia said in a security advisory posted on its Web site: http://secunia.com/advisories/22477
It is hard to exploit the flaw because it requires the attacker to lure someone to a malicious site, and for the attacker to know what other secure site the visitor might simultaneously have open, Kristensen said. "A quick user browsing through our Web site using IE7 found it failed one of our tests," he said.
The company then verified the information, notified Microsoft and published a proof-of-concept exploit on its Web site.