An anti-malware organization has called on Apple to beef up its Safari Web browser to protect users from exploits that could let attackers download malicious code to a Mac or Windows user's desktop.

Stopbadware.org, a group founded by Google, Chinese computer maker Lenovo and Sun Microsystems, on Monday asked Apple to reconsider its refusal to address the flaw as a security problem.

"StopBadware.org believes that users should have control over software being downloaded to their computers, and we encourage Apple to reconsider its stance and treat this as the security issue that it is," Stopbadware.org said in an appeal posted to its Web site.

The group's concern centered around an issue made public a week ago by Nitesh Dhanjani, a security researcher and the co-author of the book Network Security Tools. In a post to his own blog last week, Dhanjani spelled out what he called a "carpet bomb" attack possible via Safari.

According to Dhanjani, attackers could take advantage of the fact that Safari lacks an option to require a user's permission to download a file. Those attackers, Dhanjani claimed, could populate a malicious site with rogue code that in turn would automatically litter a user's desktop with malware.

Although Dhanjani praised Apple's security team for its rapid response to his queries, he also noted that the US-based computer and consumer electronics maker passed on updating Safari to lock out such attacks.

After he suggested that Apple add a setting to Safari that could be toggled to ask the user before downloads are allowed, Dhanjani said he received this reply from the company's security group: "...the ability to have a preference to 'Ask me before downloading anything' is a good suggestion. We can file that as an enhancement request for the Safari team."

However, the issue is not a security problem, said Apple. "Please note that we are not treating this as a security issue, but a further measure to raise the bar against unwanted downloads."

Other browsers, including Microsoft's Internet Explorer and Mozilla's Firefox, include options that prompt users before initiating downloads of some or all file types.

"Assuming Nitesh's analysis is accurate, 'unwanted downloads,' as Apple calls them, represent a serious security threat to users, who can be easily tricked into executing a malicious file," argued Stopbadware.org.

The group has rebuked Apple before. In March, when Apple started using its software update utility to push Safari 3.1 to Windows users, Stopbadware.org first noted the move, then later said that, following its usual practice, it had notified Apple it would soon issue a "badware" alert for the company's Software Update.

The day before Stopbadware.org was set to release that alert, Apple modified how the updater offered Safari 3.1, separating updates for already-installed programs from offers to install new software.

Apple did not reply to a request for comment on its security team's decision against adding a user-approval option to Safari.