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scan for malware on the command line

Screen Shot 2017-12-20 at 19.23.50


DetectX Swift now has the ability to do command line searches for issues on your mac like malware, keyloggers, browser hijacks and potentially dangerous software, and there’s a number of extra options that are not available when using the user interface. In this post, I’m going to give you a quick tour of the CLI (Command Line Interface) tool with some examples of how to use it (if you haven’t yet grabbed a free copy of DetectX Swift you might want to do that first to play along).

1. Basic scan
Let’s start with a basic scan. To use the CLI search, you need to specify the full path to the app executable. In this example, let’s suppose that the app is in /Applications folder. In that case, you’d need to execute this on the command line:

/Applications/DetectX\ Swift.app/Contents/MacOS/DetectX\ Swift search

Since that’s a bit of a handful, even using tab completion, you might want to edit your .bash_profile to include a shortcut alias. Here’s mine:

sphil@sphils-iMac-5:~$ cat .bash_profile

alias sudo='sudo '

alias detectx='/Applications/DetectX\ Swift.app/Contents/MacOS/DetectX\ Swift'

Note the sudo line (and note the extra space in the value). We’re going to need that so that we can pass the alias to sudo when we want to pass certain options to the search. Like…

2. Scan other users
Probably the most important benefit you gain with scanning on the command line rather than from the app’s interface is the ability to scan all, or selected, other users. You can search all users by using sudo and the -a option:

sudo detectx search -a

If you want to restrict the search to one or more users, the -u option allows you to specify a list of shortuser names (comma-delimited):

sudo detectx search -u alice,bob

3. Go deep
If you’d like more verbose output, including how long the search took, try either the vsearch or vvvv commands:

sudo detectx vvvv -a

4. Save the results
You can specify a path to output the results, either in regular text:

sudo detectx vvvv -a ~/Desktop/searchtest.txt

or, by passing the extra -j option, in JSON format:

sudo detectx search -aj ~/Desktop/searchtest.json

Here’s an example of what the formatted JSON file looks like:

Screen Shot 2017-12-20 at 18.05.26

5. Anything else?
There’s a help command that will output the documentation to the command line, and also if you get into the habit of regularly running command line checks, don’t forget to launch the app from time to time in the Finder. Like its predecessor, DetectX, DetectX Swift does a lot of other stuff besides searching that can help track down and remediate problems with your mac, and a large part of that revolves around the way it tracks changes to your system every time you launch it. The CLI tool runs independently of that and won’t give you that kind of feedback or record those changes.

Finally, note that in the release version of DetectX Swift, the CLI tool is only available for a limited period to Home and Unregistered users. Unlimited acccess to the CLI tool requires a Pro or Management license.

Enjoy! 🙂


DetectX Swift History

DetectX Swift beta has arrived

It’s been unusually quiet on Applehelpwriter these past few months, and the reason is that I’ve been devoting all my time and efforts to the new version of DetectX. The new version is called DetectX Swift because (yeah, you guessed it) I wrote it in Swift and because it’s considerably faster than its older sibling.

DetectX Swift’s got a new interface, but there’s far more going on under the hood. The Search uses some fancy heuristics as well as hard-coded and live update search definitions to ensure it provides the very best in security threat scanning.

The new Profile view employs some super cool dynamic highlighting and lets you inspect the contents not only of directories but also of scripts, plists and other files that could execute troublesome code on your mac.

There’s changes in the History view, too, both in the display and functions. One of the coolest things I like about the new History function is that you can run a diff on any previous run against the latest run, immediately seeing how they differ.

There’s tons more to DetectX Swift, but the best way to find out about it is just to try it. The beta version is free to use for both Home and Commercial users, so just head off over to its home page and grab yourself a copy!

Don’t forget to keep us informed of how it goes. The beta is still in an early stage and more features are slated as it develops, but feel free to tell us about anything that you feel could be done better or things that you’d like to see added.

Share and enjoy! 🙂

how to reveal hidden users


With malware big in the news again, and evidence that at least one malware variant that targets macOS creates hidden users on the victim’s system, here’s a timely tip on how to check for unwelcome guests.

For this tip, we’re going to use the Terminal, which you can find in the /Applications/Utilities folder. If you’re not a frequent visitor to the land of the command line, you might want to see my 3-part series “Learning the Terminal”.

Regardless, the first thing we’re going to do in Terminal is about the simplest command you’ll ever type: w. Yep, type a single ‘w’ at the prompt and press return.





The w utility is a very quick way to see who’s currently logged on to your system and to ensure that there’s no surprises. You should see a couple of entries for yourself: one as ‘console’ and one as ‘s***’. The first represents a login through the usual Desktop GUI login window; the second is there because you just logged into Terminal. Anybody else logged in either via the command line (like a potential remote user) or the GUI will show up here. Notice that on my machine, there’s another user called ‘Developer’ who hasn’t logged in using the GUI, but is logged in via a command line interface. Note that ‘w’ returns the full user name, not the short one.

While the w utility will tell you if a hidden user is currently logged on, what if there’s a hidden user that isn’t active at the particular time you check? To look for those, we have a couple of options. First, we can use the dscl utility to list all users, and you might be surprised at how many there are:

dscl . -list /Users

Look to the end of that list where the names that don’t begin with an underscore start. ‘Daemon’, ‘Nobody’, ‘Root’ and ‘Guest’ are all standard system accounts, as are all those entries that begin with an underscore. Don’t worry about those. However, aside from those, you should only see names that you recognise. To make things a little easier, we can add another command to the dscl command to filter that list. Try this

dscl . -list /Users | grep -vE ‘_|root|nobody|daemon|Guest’

That should now only return the names of real users. There shouldn’t be any names in there you don’t recognise. In my example, I know the last three, but the first one ‘dev’ isn’t familiar to me. Note that unlike ‘w’, this command returns short user names, and that ‘dev’ looks very much like it’s the same account as ‘Developer’ that I saw earlier.




However, what we have so far is a list of users, not a list of hidden users. To see specifically if any accounts are hidden, we need a longer command:

defaults read /Library/Preferences/com.apple.loginwindow

Normally, when there are no hidden users, this will return the contents of a property list file that may look something like this:

{
GuestEnabled = 1;
OptimizerLastRunForBuild = 31898816;
OptimizerLastRunForSystem = 168494592;
SHOWFULLNAME = 1;
lastUser = loggedIn;
lastUserName = imackim;
}




That tells us that there’s no hidden users on this mac. How so? Because if there were it would return something very different, like this:





We can see not only the list of hidden users, but also that the preference for hiding users has been set to ‘1’ (in plist syntax, ‘1’ means true and ‘0’ means false). Note again that unlike the dscl command above, this returns the account’s full name, not the short user name.

If we’d like to ‘unhide’ that user, so the account appears in the login window GUI and in System Preferences’ ‘Users & Groups’ pane, we’ll need admin privileges. To do that, cut and paste the following into Terminal:

sudo defaults write /Library/Preferences/com.apple.loginwindow Hide500Users -bool NO

Supply an admin user password at the prompt and hit ‘return’, but type slowly as the display doesn’t register your key presses, which makes it easy to fat finger your password.



For the more advanced
We can save ourselves some typing by putting much of this into a script so that we can run it whenever we want. If you’re not familiar with how to create and use bash scripts, take a look here.

Our script will basically do the same as all the commands we listed above (except changing the prefs for Hide500Users) in one fell swoop, and there’s a couple of little twists that I’ll leave as an exercise for the reader to figure out. To save on the typing, you can copy the whole script from my pastebin here.



The script’s output is illustrated in the shot at the top of this post.

Enjoy! 🙂

how to recover from OSX/Dok malware – updated





Last updated: May 10th, 2017 to include Dok.B variant.

There’s been a lot of drama the last few days over a new malware attack on macOS.

There’s FOUR steps to removing the malware.

1. Remove the installed files
Both my apps, DetectX and FastTasks 2 will detect this malware, and remove the appropriate files. For those of you that like to do things by hand, here’s the list of things to look for. You may find some and not others. Any you do find need to be removed:

~/Downloads/Dok.zip

~/Downloads/Dok/Dokument/Contents

~/Library/Containers/.bella/Bella

~/Library/Containers/.bella/bella.db

~/Library/LaunchAgents/com.apple.iTunes.plist

~/Library/LaunchAgents/com.apple.Safari.pac.plist

~/Library/LaunchAgents/com.apple.Safari.proxy.plist

/Library/Containers/.bella/Bella

/Library/Containers/.bella/bella.db

/usr/local/bin/SafariProxy

/Users/Shared/AppStore.app

You might also want to remove the dead ‘AppStore.app’ login item (if it’s still there) from System Preferences | Users & Groups | Login Items.


2. Remove the network proxy redirecting your internet traffic
Victims also need to remove the sneaky proxy that’s redirecting their internet traffic from System Preferences’ Network pane. While this can be done manually, it’s a lot of clicking, especially since you must do it for all services. Easier, then, to use this AppleScript. Note it will need an Admin password.

Get the script from my pastebin (if you copy and paste from a webpage like this and the script won’t compile, get the source from pastebin).


###########################################################
-->> ABOUT
###########################################################
(*

Phil Stokes -- 2017
applehelpwriter.com
sqwarq.com

*)
###########################################################
-->> DESCRIPTION
###########################################################
(*

Turn off the Automatic Proxy Configuration in Network System Preferences.

*)
###########################################################
-->> USAGE
###########################################################
(*

Requires Admin password.
This script was developed primarily as part of a remedy for victims of OSX/Dok malware.

*)
###########################################################
-->> COMMANDS
###########################################################

set services to paragraphs of (do shell script "networksetup -listallnetworkservices")
set autoproxyURL to " 0.0.0.0"
set autoproxySERVICE to ""
repeat with i from 2 to (count of services)
set autoproxySERVICE to item i of services as text
do shell script ("networksetup -setautoproxyurl " & (quoted form of autoproxySERVICE) & autoproxyURL) with administrator privileges
do shell script ("networksetup -setautoproxystate " & (quoted form of autoproxySERVICE) & " off") with administrator privileges
end repeat

###########################################################
#EOF

If you’re not comfortable running AppleScripts, you can do it manually as shown in the screenshot below, but remember you need to go through and do the procedure for every one of your services (Ethernet, Wi-Fi, Bluetooth Pan, etc) individually.






3. Remove the fake certificate
Thirdly, you’ll want to get rid of the fake certificate in the System keychain. In Terminal, search to see if the ‘cert.der’ certificate file still exists:

cd /tmp; ls -alF

If you see ‘cert.der’ listed, then issue the following command in the Terminal window:

security remove-trusted-cert -d /tmp/cert.der

Then, go back to Terminal and do

rm /tmp/cert.der

If not, then try both this

security remove-trusted-cert -D

and check in Keychain Access.app by searching for ‘Comodo’ and looking for a certificate that has the fake Comodo serial number:
00 EB 08 6A 4F 53 BE BA 4D.



4. Remove permissive admin access set by the malware
Back to Terminal for this one, and mind your typing. You don’t want to make any mistakes here…

At the command line prompt, type

sudo visudo

and provide an Admin user name. You won’t be able to see what you type, so type slowly, but at least you get 3 goes at it.

When you’ve got that in correctly, you should see the sudoers file, it’ll look something like this:





Use the arrow key to move the cursor down to the beginning of the line that says

%USER_NAME_HERE%  ALL=(ALL) NOPASSWD: ALL

On your keyboard hit the ‘d’ key twice (i.e, type dd). The line should magically disappear*.

Finally, type

:wq!

(that’s a semi-colon, a lowercase w, lowercase q and an exclamation mark) to save your changes and quit. That’s it!

And with that, you should be done with OSX/Dok malware! 🙂



*If anything went wrong in visudo, you can press the u key once to undo your last action (the ‘u’ key only undoes the last keyboard action, so if you press it twice it’ll undo the undo = redo, so beware!)


news: DetectX v2.14 released

Screen Shot 2016-02-14 at 23.03.29

Yes, two in two days! We’ve added a Preference Pane since yesterday, and improved the performance of the search function. Note that the new Sparkle Vulnerability check we introduced in v2.13 is now off by default. It can be turned on from the Preference Pane (see above).

Other changes are listed in the release notes.

DetectX is still free, fully-functional, and without time-limit for home users. Available for download from here.

🙂

 

news: DetectX 2.12 released

We just released an update to DetectX, available for free download from here. The release notes are here.

how to detect WireLurker malware

wirelurker malware


Security researchers have this week been getting themselves het up about a new malware threat to both iOS and OS X. WireLurker appears to be emanating out of Chinese file exchange sites and, at least at the moment, looks fairly limited in both its spread and its damage (update: Business Insider is reporting that Apple has blocked WireLurker-infected apps from launching).

However, researchers at Paolo Alto Networks are pointing out that what makes WireLurker particularly worrying is that the malware exploits weaknesses in Apple’s software that could, they claim, be easily be used for far more dangerous threats.

You can easily scan for the malware threat with my free app FastTasks 2 (v 1.53 or later). If you don’t see the warning as in the screenshot above or any results in the Analyser ‘Issues’ pane, you’re clean of any of the currently known files associated with WireLurker. If you do see the warning, locate the infectious files from the Analyser pane and delete (OS X will demand your Admin password to remove some of them), then restart your mac.

🙂


protect your mac from malware, viruses and other threats

Nessus Vulnerability Software

If you’re new to Mac, you’re probably thinking that it’s a no-brainer that you need some kind of anti-virus app. Once you start looking around the web for reviews, it’s inevitable that you’re going to come across the Great Mac AntiVirus Debate: in the one corner, those who say Mac users who forego antivirus protection are arrogant and just setting themselves up for a fall, and in the other those who’ve used Macs for umpteen years, never had or heard of any real threat, and consequently say AV software is a waste of time.

You can read round this debate for years and never come to a satisfying conclusion, largely because its as much about what you ‘ought’ to do as it is about what is the case. Just because you’ve never had any viruses, doesn’t mean you won’t get one tomorrow. And yet, there are NO viruses in the wild known to affect macs, and so when one does arrive, it will be unknown to your AV scanner. Hence, an AV Scanner is just a waste of system resources (and possibly money, if you paid for it). Yikes! What do I do!!

What you do is sidestep the whole debate and stop thinking only about virus scanners, which after all deal with only a small subset of all the possible attack vectors in the internet age, and start thinking in terms of vulnerability scanners. Unlike a simple virus scanner, a vulnerability scanner examines your system not only for malware but also for any vulnerabilities in commercial software, plug ins, your system setup (including network and other sharing settings) and other installed items. The scanner will not only explain the threat and its severity but also tell you what, if anything, you need to do, recommend patches and guide you to links for more info where available.

You can use something like Nessus for free if you are a home user, which will give you a far better insight into the possible attacks someone could implement on your system (and it will check your system against almost all of the major virus scanner databases like Symantec, etc).

Even better, a vulnerability scanner like Nessus won’t just examine your machine, it’ll look at everything else (and all the installed apps) of anything on your home network including phones (any platform), other computer systems (any OS), and even your router.

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