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A security researcher has revealed details of a new piece of undetectable malware targeting Apple's Mac computers—reportedly first macOS malware of 2018.

Dubbed OSX/MaMi, an unsigned Mach-O 64-bit executable, the malware is somewhat similar to DNSChanger malware that infected millions of computers across the world in 2012.

DNSChanger malware typically changes DNS server settings on infected computers, allowing attackers to route internet traffic through malicious servers and intercept sensitive information.

First appeared on the Malwarebytes forum, a user posted a query regarding unknown malware that infected his friend's computer that silently changed DNS settings on infected macOS to 82.163.143.135 and 82.163.142.137 addresses.

After looking at the post, ex-NSA hacker Patrick Wardle analysed the malware and found that it is indeed a 'DNS Hijacker,' which also invokes security tools to install a new root certificate in an attempt to intercept encrypted communications as well.

"OSX/MaMi isn't particularly advanced - but does alter infected systems in rather nasty and persistent ways," Patrick said.

"By installing a new root certificate and hijacking the DNS servers, the attackers can perform a variety of nefarious actions such as man-in-the-middle'ing traffic (perhaps to steal credentials, or inject ads)" or to insert cryptocurrency mining scripts into web pages.

Besides this, the OSX/MaMi macOS malware, which appears to be in its initial stage, also includes below-mentioned abilities, most of which are not currently activated in its version 1.1.0:

• Take screenshots
• Generate simulated mouse events
• Perhaps persist as a launch item
• Download and upload files
• Execute commands

However, Patrick believes that the attackers could be using lame methods like malicious emails, web-based fake security alerts/popups, or social-engineering type attacks to target Mac users.

To check if your Mac computer is infected with MaMi malware, go to the terminal via the System Preferences app and check for your DNS settings—particularly look for 82.163.143.135 and 82.163.142.137.

According to VirusTotal, a multi-engine antivirus scanner, none of 59 popular antivirus software is detecting this malware at this moment, so you are advised to use a 3rd-party tool such as a firewall that can detect and block outgoing traffic.

You can also install a free open-source firewall for macOS named 'LuLu,' created by Patrick and available at GitHub, which blocks suspicious traffic and prevents OSX/MaMi's from stealing your data.

Yet another password vulnerability has been uncovered in macOS High Sierra, which unlocks App Store System Preferences with any password (or no password at all).

A new password bug has been discovered in the latest version of macOS High Sierra that allows anyone with access to your Mac to unlock App Store menu in System Preferences with any random password or no password at all.

The impact of this vulnerability is nowhere as serious as the previously disclosed root login bug in Apple's desktop OS that enabled access to the root superuser account simply by entering a blank password on macOS High Sierra 10.13.1.

As reported on Open Radar earlier this week, the vulnerability impacts macOS version 10.13.2 and requires the attacker to be logged in with an administrator-level account for this vulnerability to work.

I checked the bug on my fully updated Mac laptop, and it worked by entering a blank password as well as any random password.

If you're running latest macOS High Sierra, check yourself:

• Log in as a local administrator
• Go to System Preferences and then App Store
• Click on the padlock icon (double-click on the lock if it is already unlocked)
• Enter any random password (or leave it blank) in login window
• Click Unlock, Ta-da!

Once done, you'll gain full access to App Store settings, allowing you to modify settings like disabling automatic installation of macOS updates, app updates, system data files and even security updates that would patch vulnerabilities.

We also tried to reproduce the same bug on the latest developer beta 4 of macOS High Sierra 10.13.3, but it did not work, suggesting Apple probably already knows about this issue and you'll likely get a fix in this upcoming software update.

What's wrong with password prompts in macOS? It's high time Apple should stop shipping updates with such an embarrassing bug.

Apple also patched a similar vulnerability in October in macOS, which affected encrypted volumes using APFS wherein the password hint section was showing the actual password of the user in the plain text.

A security researcher on New Year's eve made public the details of an unpatched security vulnerability in Apple's macOS operating system that can be exploited to take complete control of a system.

On the first day of 2018, a researcher using the online moniker Siguza released the details of the unpatched zero-day macOS vulnerability, which he suggests is at least 15 years old, and proof-of-concept (PoC) exploit code on GitHub.

The bug is a serious local privilege escalation (LPE) vulnerability that could enable an unprivileged user (attacker) to gain root access on the targeted system and execute malicious code. Malware designed to exploit this flaw could fully install itself deep within the system.

From looking at the source, Siguza believes this vulnerability has been around since at least 2002, but some clues suggest the flaw could actually be ten years older than that. "One tiny, ugly bug. Fifteen years. Full system compromise," he wrote.

This local privilege escalation flaw resides in IOHIDFamily, an extension of the macOS kernel which has been designed for human interface devices (HID), like a touchscreen or buttons, allowing an attacker to install a root shell or execute arbitrary code on the system.

"IOHIDFamily has been notorious in the past for the many race conditions it contained, which ultimately lead to large parts of it being rewritten to make use of command gates, as well as large parts being locked down by means of entitlements," the researcher explains.

"I was originally looking through its source in the hope of finding a low-hanging fruit that would let me compromise an iOS kernel, but what I didn’t know it then is that some parts of IOHIDFamily exist only on macOS - specifically IOHIDSystem, which contains the vulnerability."

The exploit created by Siguza, which he dubbed IOHIDeous, affects all versions of macOS and enables arbitrary read/write bug in the kernel.

Besides this, IOHIDeous also disables the System Integrity Protection (SIP) and Apple Mobile File Integrity (AMFI) security features that offer protection against malware.

The PoC code made available by Siguza has for some reason stopped working on macOS High Sierra 10.13.2 and works on macOS High Sierra 10.13.1 and earlier, but he believes the exploit code can be tweaked to work on the latest version as well.

However, the researcher pointed out that for his exploit to work, it needs to force a log out of the logged-in user, but this can be done by making the exploit work when the targeted machine is manually shut down or rebooted.

Since the vulnerability only affects macOS and is not remotely exploitable, the researcher decided to dumped his findings online instead of reporting it to Apple. For those unaware, Apple's bug bounty program does not cover macOS bugs.

For in-depth technical details about the vulnerability, you can head on to researcher's write-up on GitHub.

If you own a Mac computer and run the latest version of Apple's operating system, macOS High Sierra, then you need to be extra careful with your computer.

A serious, yet stupid vulnerability has been discovered in macOS High Sierra that allows untrusted users to quickly gain unfettered administrative (or root) control on your Mac without any password or security check, potentially leaving your data at risk.

Discovered by developer Lemi Orhan Ergin on Tuesday, the vulnerability only requires anyone with physical access to the target macOS machine to enter "root" into the username field, leave the password blank, and hit the Enter a few times—and Voila!

In simple words, the flaw allows an unauthorized user that gets physical access on a target computer to immediately gain the highest level of access to the computer, known as "root," without actually typing any password.

Needless to say, this blindingly easy Mac exploit really scary stuff.

This vulnerability is similar to one Apple patched last month, which affected encrypted volumes using APFS wherein the password hint section was showing the actual password of the user in the plain text.

Here's How to Login as Root User Without a Password

If you own a Mac and want to try this exploit, follow these steps from admin or guest account:

• Open System Preferences on the machine.
• Select Users & Groups.
• Click the lock icon to make changes.
• Enter "root" in the username field of a login window.
• Move the cursor into the Password field and hit enter button there few times, leaving it blank.

With that (after a few tries in some cases) macOS High Sierra logs the unauthorized user in with root privileges, allowing the user to access your Mac as a "superuser" with permission to read and write to system files, including those in other macOS accounts as well.

This flaw can be exploited in several ways, depending on the setup of the targeted Mac. With full-disk encryption disabled, a rogue user can turn on a Mac that's entirely powered down and log in as root by doing the same trick.

At Mac's login screen, an untrusted user can also use the root trick to gain access to a Mac that has FileVault turned on to make unauthorized changes to the Mac System Preferences, like disabling FileVault.

All the untrusted user needs to do is click "Other" at the login screen, and then enter "root" again with no password.

However, it is impossible to exploit this vulnerability when a Mac machine is turned on, and the screen is protected with a password.

Ergin publicly contacted Apple Support to ask about the issue he discovered. Apple is reportedly working on a fix.

"We are working on a software update to address this issue. In the meantime, setting a root password prevents unauthorized access to your Mac. To enable the Root User and set a password, please follow the instructions here: https://support.apple.com/en-us/HT204012. If a Root User is already enabled, to ensure a blank password is not set, please follow the instructions from the 'Change the root password' section."

Here's How to Temporarily Fix the macOS High Sierra Bug

Fortunately, the developer suggested a temporary fix for this issue which is as easy as its exploit.

To fix the vulnerability, you need to enable the root user with a password. Heres how to do that:

• Open System Preferences and Select Users & Groups
• Click on the lock icon and Enter your administrator name and password there
• Click on "Login Options" and select "Join" at the bottom of the screen
• Select "Open Directory Utility"
• Click on the lock icon to make changes and type your username and password there
• Click "Edit" at the top of the menu bar
• Select "Enable Root User" and set a password for the root user account

This password will prevent the account from being accessed with a blank password.

Just to be on the safer side, you can also disable Guest accounts on your Mac. for this, head on to System Preferences → Users & Groups, select Guest User after entering your admin password, and disable "Allow guests to log in to this computer."

A severe programming error has been discovered in Apple's latest macOS High Sierra 10.13 that exposes passwords of encrypted Apple File System (APFS) volumes in plain text.

Reported by Matheus Mariano, a Brazilian software developer, the vulnerability affects encrypted volumes using APFS wherein the password hint section is showing the actual password in the plain text.

Yes, you got that right—your Mac mistakenly reveals the actual password instead of the password hint.

In September, Apple released macOS High Sierra 10.13 with APFS (Apple File System) as the default file system for solid-state drives (SSDs) and other all-flash storage devices, promising strong encryption and better performance.

Mariano discovered the security issue while he was using the Disk Utility in macOS High Sierra to add a new encrypted APFS volume to a container. When adding a new volume, he was asked to set a password and, optionally, write a hint for it.

So, whenever the new volume is mounted, macOS asks the user to enter the password.

However, Mariano noticed that when he clicked the "Show Hint" button, he was served with his actual password in the plain text rather than the password hint.

You can see the demonstration of the problem in the below-given video:
This security issue is not the only one discovered in Apple's latest desktop operating system.

Just a few hours before the release of High Sierra, ex-NSA hacker Patrick Wardle publicly disclosed the details of a separate critical vulnerability that allows installed apps to steal passwords and secret data from the macOS keychain.

The good news is that Apple released a supplemental macOS High Sierra 10.13 update on Thursday to addressed both the issues. Mac users can install update from the Mac App Store or download it from the Apple's Software site.

It should be noted that just installing the update would not solve the APFS password disclosure issue. Apple has published a user guide on the password disclosure bug, which you should follow to protect your data.

Apple yesterday rolled out a new version of its macOS operating system, dubbed High Sierra 10.13—a few hours before an ex-NSA hacker publicly disclosed the details of a critical vulnerability that affects High Sierra as well as all earlier versions of macOS.

Patrick Wardle, an ex-NSA hacker and now head of research at security firm Synack, found a critical zero-day vulnerability in macOS that could allow any installed application to steal usernames and plaintext passwords of online accounts stored in the Mac Keychain.

The macOS Keychain is a built-in password management system that helps Apple users securely store passwords for applications, servers, websites, cryptographic keys and credit card numbers—which can be accessed using only a user-defined master password.

Typically no application can access the contents of Keychain unless the user enters the master password.

"I discovered a flaw where malicious non-privileged code (or apps) could programmatically access the keychain and dump all this data .... including your plain text passwords. This is not something that is supposed to happen!," Wardle said.

Wardle yesterday posted a proof-of-concept video of the exploit, demonstrating how the hack can be used to exfiltrate every single plaintext password from Keychain without requiring the user to enter the master password.
The video shows how a malicious installed application, signed or unsigned, allowed an attacker to remotely steal all the passwords stored in the keychain and does not notify the user of the attack either.

"macOS is designed to be secure by default, and Gatekeeper warns users against installing unsigned apps, like the one shown in this proof of concept, and prevents them from launching the app without explicit approval," said Apple in a statement released today.

"We encourage users to download software only from trusted sources like the Mac App Store and to pay careful attention to security dialogs that macOS presents."

Wardle claimed that he reported the issue to Apple last month, and made the public disclosure when the company planned to release High Sierra without fixing the vulnerability, which not only affects the newest version but also older versions of macOS.

Earlier this month Patrick disclosed another flaw in macOS High Sierra's kernel extension SKEL (Secure Kernel Extension Loading) security feature that could allow an attacker to run any third-party at kernel level extension without requiring user approval.