Kaspersky Lab security researchers have discovered a vulnerability in the kernel of Darwin – an open-source component of both the OS X and iOS operating systems. This “Darwin Nuke” vulnerability leaves OS X 10.10 and iOS 8 devices exposed to remotely-activated denial of service (DoS) attacks that can damage the user’s device and impact any corporate network to which it is connected.
The experts call on users to update devices with the OS X 10.10.3 and iOS 8.3 software releases, which no longer include this vulnerability.
Analysis of the vulnerability by Kaspersky Lab revealed that the devices affected by the threat include those with 64-bit processors and iOS 8: iPhone 5s, iPhone 6, iPhone 6 Plus, iPad Air, iPad Air 2, iPad mini 2, and iPad mini 3.
The “Darwin Nuke” vulnerability is exploited while processing an IP packet of specific size and with invalid IP options. Remote attackers can initiate a DoS (denial of service) attack on a device with OS X 10.10 or iOS 8, sending an incorrect network packet to the target.
After processing the invalid network packet, the system will crash. Kaspersky Lab’s researchers discovered that the system will crash only if the IP packet meets the following conditions:
- The size of the IP header should be 60 bytes.
- The size of the IP payload should be less than or equal to 65 bytes.
- The IP options should be incorrect (invalid option size, class, etc.)
“At first sight, it is very hard to exploit this bug, as the conditions attackers need to meet are not trivial ones. But persistent cybercriminals can do so, breaking down devices or even affecting the activity of corporate networks,“ said Anton Ivanov, Senior Malware Analyst at Kaspersky Lab.
“Routers and firewalls would usually drop incorrect packets with invalid option sizes, but we discovered several combinations of incorrect IP options that are able to pass through the Internet routers. We’d like to warn all OS X 10.10 and iOS 8 users to update devices to OS X 10.10.3 and iOS 8.3 releases,” Ivanov added.
Kaspersky Lab’s products protect OS X against the “Darwin Nuke” vulnerability with the Network Attack Blocker feature. Starting with Kaspersky Internet Security for Mac 15.0, this threat is detected as DoS.OSX.Yosemite.ICMP.Error.exploit.
Kaspersky Lab’s tips for boosting the security of Mac devices include:
- Use a web browser that has a solid track record of fixing security issues promptly.
- Run "Software Update" and patch the machine promptly when updates are available.
- Use a password manager to help cope with phishing attacks.
- Install a good security solution.