Just because you’re using a Mac doesn’t mean you’re safe from hackers. That’s what two security researchers are warning, after finding a Mac-based malware that may be an attempt by Iranian hackers to target the U.S. defense industry.

The malware, called MacDownloader, was found on a website impersonating the U.S. aerospace company United Technologies, according to a report from Claudio Guarnieri and Collin Anderson, who are researching Iranian cyberespionage threats.

[ To comment on this story, visit Computerworld's Facebook page. ]

The fake site was previously used in a spear-phishing email attack to spread Windows malware and is believed to be maintained by Iranian hackers, the researchers claimed.

Visitors to the site are greeted with a page about free programs and courses for employees of the U.S. defense companies Lockheed Martin, Raytheon and Boeing.

The malware itself can be downloaded from an Adobe Flash installer for a video embedded in the site. The website will provide either Windows or Mac-based malware, depending on the detected operating system.

Iran Threats A screenshot of the fake site.

The MacDownloader malware was designed to profile the victim's computer, and then steal credentials by generating fake system login boxes and harvesting them from Apple's password management system, Keychain.

However, the malware is of shoddy quality and is "potentially a first attempt from an amateur developer," the researchers said.

For instance, once the malware is installed, it will generate a fake Adobe Flash Player dialog box, only to then announce that adware was discovered on the computer and that it will attempt to clean it up.

"These dialogues are also rife with basic typos and grammatical errors, indicating that the developer paid little attention to quality control," the researchers said.

In addition, the malware failed to run a script to download additional malicious coding onto the infected Mac.

But despite the shoddy quality, the malware still managed to evade detection on VirusTotal, which aggregates antivirus scanning engines.

The researchers found other circumstantial evidence that the malware is linked to Iran. An exposed server that the MacDownloader agent uploaded showed wireless networks called "Jok3r" and "mb_1986." Both of these names have ties to previous Iranian hacking groups, including one known as Flying Kitten, which is suspected of targeting U.S. defense contractors and political dissidents.

In an email, Anderson said a colleague also observed MacDownloader targeting a human rights activist.

The danger is that many human rights supporters, especially in Iran, are dependent on Apple devices, the researchers said. "While this [malware] is neither sophisticated nor full-featured, its sudden appearance is concerning given the popularity of Apple computers," they wrote in their report.

Mac malware is fairly rare, according to security researchers. That's because hackers tend to attack Windows-based devices, because of their popularity.

However, Mac-based malware is still popping up here and there. Last month, researchers found another kind designed to spy on biomedical research centers. A separate Mac-based Trojan was found months earlier, targeting the aerospace industry.