How to remove the SysJoker malware from your operating system
Written by Tomas Meskauskas on (updated)
What is SysJoker?
SysJoker is a backdoor-type malicious program. It operates by injecting compromised systems with other malware. SysJoker is also a cross-platform program; hence, in addition to macOS, it also targets Windows and Linux operating systems.
SysJoker overview
At the time of writing, SysJoker's capabilities were the same regardless of the infected platform. As mentioned in the introduction, this malicious program is designed to cause chain infections (i.e., download/install additional malware).
To expand upon the most common malicious software, "trojan" is a term that defines an incredibly varied type of malware. Trojans may be able to exfiltrate content (files and data) from the system, extract information from browsers and other installed applications, record keystrokes (keylogging), record/livestream the desktop or audio/video via microphones and cameras, enable remote control over devices (RATs - Remote Access Trojans), and so on.
Ransomware encrypts data and demands ransoms for the decryption (screenlocker types may not encrypt files and instead just lock the screen for the same purpose). Cryptominers are malicious programs that abuse system resources (potentially to the point of system failure) to generate cryptocurrency.
To summarize, infections with malware like SysJoker, can lead to data loss, hardware damage, serious privacy issues, financial losses, and identity theft.
| Name | SysJoker virus |
| Threat Type | Mac malware, Mac virus, Trojan, password-stealing virus, spyware. |
| Detection Names | Avast (MacOS:Joker-A [Trj]), Combo Cleaner (Trojan.GenericKD.47868192), ESET-NOD32 (OSX/SysJoker.A), Kaspersky (HEUR:Backdoor.OSX.SysJoker.gen), Full List Of Detections (VirusTotal) |
| Symptoms | Trojans-type malware is designed to stealthily infiltrate the victim's computer and remain silent, and thus no particular symptoms are clearly visible on an infected machine. |
| Distribution Methods | Infected email attachments, fake Adobe Flash Player installers, malicious online advertisements, social engineering, software 'cracks'. |
| Damage | Data and financial losses, loss of access to personal accounts, problems with browsing safety, online privacy issues. |
| Malware Removal (Mac) | To eliminate possible malware infections, scan your Mac with legitimate antivirus software. Our security researchers recommend using Combo Cleaner. |
Mac malware examples
macOS.Macma and OceanLotus are a couple examples of programs similar to SysJoker. Theoretically, backdoor malware can infect devices with any type of malware. However, they may have certain limitations or be designed to inject specific programs into systems. UpdateAgent, Silver Sparrow, Tarmac, and OSAMiner are a few other Mac-specific malicious programs.
How did SysJoker infiltrate my computer?
Malware is spread using phishing and social engineering methods. To elaborate, spam campaigns are commonly used for this purpose. Spam emails can have malicious files attached to and/or linked inside them. Virulent files can be executables, archives, PDF and Microsoft Office documents, JavaScript, etc. Malicious software download/installation is jumpstarted - once these files are opened.
Malware is also proliferated through untrustworthy download channels, e.g., unofficial and free file-hosting websites, Peer-to-Peer (P2P) sharing networks, and other third-party downloaders.
Illegal activation ("cracking") tools and fake updates are used in distribution as well. "Cracks" can cause infections instead of activating licensed products. Fraudulent updaters infect systems by abusing outdated software weaknesses and/or by installing malicious programs.
How to avoid installation of malware?
The attachments and links found in suspicious and irrelevant emails - must not be opened, as they are potential sources of infection. It is advised to always download from official and verified sources. Additionally, all programs must be activated and updated with tools/functions provided by legitimate developers.
It is paramount to have a reputable anti-virus installed and kept updated. This software has to be used to run regular system scans and to remove detected threats. If your computer is already infected with malware, we recommend running a scan with Combo Cleaner Antivirus for macOS to automatically eliminate them.
Instant automatic Mac malware removal:
Manual threat removal might be a lengthy and complicated process that requires advanced IT skills. Combo Cleaner is a professional automatic malware removal tool that is recommended to get rid of Mac malware. Download it by clicking the button below:
▼ DOWNLOAD Combo Cleaner for Mac
By downloading any software listed on this website you agree to our Privacy Policy and Terms of Use. To use full-featured product, you have to purchase a license for Combo Cleaner. Limited seven days free trial available. Combo Cleaner is owned and operated by Rcs Lt, the parent company of PCRisk.com read more.
Quick menu:
- What is "SysJoker"?
- STEP 1. Remove PUA related files and folders from OSX.
- STEP 2. Remove rogue extensions from Safari.
- STEP 3. Remove rogue add-ons from Google Chrome.
- STEP 4. Remove potentially unwanted plug-ins from Mozilla Firefox.
Video showing how to remove adware and browser hijackers from a Mac computer:
Potentially unwanted applications removal:
Remove potentially unwanted applications from your "Applications" folder:
Click the Finder icon. In the Finder window, select "Applications". In the applications folder, look for "MPlayerX","NicePlayer", or other suspicious applications and drag them to the Trash. After removing the potentially unwanted application(s) that cause online ads, scan your Mac for any remaining unwanted components.
Remove adware-related files and folders
Click the Finder icon, from the menu bar. Choose Go, and click Go to Folder...
Check for adware generated files in the /Library/LaunchAgents/ folder:
In the Go to Folder... bar, type: /Library/LaunchAgents/
In the "LaunchAgents" folder, look for any recently-added suspicious files and move them to the Trash. Examples of files generated by adware - "installmac.AppRemoval.plist", "myppes.download.plist", "mykotlerino.ltvbit.plist", "kuklorest.update.plist", etc. Adware commonly installs several files with the exact same string.
Check for adware generated files in the ~/Library/Application Support/ folder:
In the Go to Folder... bar, type: ~/Library/Application Support/
In the "Application Support" folder, look for any recently-added suspicious folders. For example, "MplayerX" or "NicePlayer", and move these folders to the Trash.
Check for adware generated files in the ~/Library/LaunchAgents/ folder:
In the Go to Folder... bar, type: ~/Library/LaunchAgents/
In the "LaunchAgents" folder, look for any recently-added suspicious files and move them to the Trash. Examples of files generated by adware - "installmac.AppRemoval.plist", "myppes.download.plist", "mykotlerino.ltvbit.plist", "kuklorest.update.plist", etc. Adware commonly installs several files with the exact same string.
Check for adware generated files in the /Library/LaunchDaemons/ folder:
In the "Go to Folder..." bar, type: /Library/LaunchDaemons/
In the "LaunchDaemons" folder, look for recently-added suspicious files. For example "com.aoudad.net-preferences.plist", "com.myppes.net-preferences.plist", "com.kuklorest.net-preferences.plist", "com.avickUpd.plist", etc., and move them to the Trash.
Scan your Mac with Combo Cleaner:
If you have followed all the steps correctly, your Mac should be clean of infections. To ensure your system is not infected, run a scan with Combo Cleaner Antivirus. Download it HERE. After downloading the file, double click combocleaner.dmg installer. In the opened window, drag and drop the Combo Cleaner icon on top of the Applications icon. Now open your launchpad and click on the Combo Cleaner icon. Wait until Combo Cleaner updates its virus definition database and click the "Start Combo Scan" button.
Combo Cleaner will scan your Mac for malware infections. If the antivirus scan displays "no threats found" - this means that you can continue with the removal guide; otherwise, it's recommended to remove any found infections before continuing.
After removing files and folders generated by the adware, continue to remove rogue extensions from your Internet browsers.
Remove malicious extensions from Internet browsers
Remove malicious Safari extensions:
Open the Safari browser, from the menu bar, select "Safari" and click "Preferences...".
In the preferences window, select "Extensions" and look for any recently-installed suspicious extensions. When located, click the "Uninstall" button next to it/them. Note that you can safely uninstall all extensions from your Safari browser - none are crucial for regular browser operation.
- If you continue to have problems with browser redirects and unwanted advertisements - Reset Safari.
Remove malicious extensions from Google Chrome:
Click the Chrome menu icon 
(at the top right corner of Google Chrome), select "More Tools" and click "Extensions". Locate all recently-installed suspicious extensions, select these entries and click "Remove".
- If you continue to have problems with browser redirects and unwanted advertisements - Reset Google Chrome.
Remove malicious extensions from Mozilla Firefox:
Click the Firefox menu 
(at the top right corner of the main window) and select "Add-ons and themes". Click "Extensions", in the opened window locate all recently-installed suspicious extensions, click on the three dots and then click "Remove".
- If you continue to have problems with browser redirects and unwanted advertisements - Reset Mozilla Firefox.
Frequently Asked Questions (FAQ)
My computer is infected with SysJoker malware, should I format my storage device to get rid of it?
No, such drastic measures are not required for SysJoker's removal.
What are the biggest issues that SysJoker malware can cause?
What danger a piece of malicious software poses - depends on its features and the cyber criminals' modus operandi. SysJoker is designed to cause chain infections; hence, its infections can lead to diminished system performance, data loss, hardware damage, serious privacy issues, financial losses, and identity theft.
What is the purpose of SysJoker malware?
In nearly all cases, malware only aims to generate revenue at its victims' expense. Other potential reasons for the release of malicious programs include: political/geopolitical motivations, personal reasons (e.g., vendettas against certain individuals, etc.), disruption of specific processes (e.g., websites, services, companies, organizations, etc.), or simply the cyber criminals' amusement.
How did SysJoker malware infiltrate my computer?
Malicious software is distributed using phishing and social engineering. It is spread via drive-by (deceptive and stealthy) downloads, online scams, unofficial and freeware download sites, Peer-to-Peer sharing networks (Torrent clients, eMule, etc.), spam mail, illegal program activation tools ("cracks"), fake updates, and so forth. Some harmful programs are capable of self-proliferating through local networks and removable storage devices (e.g., external hard drives, USB flash drives, and similar).
Will Combo Cleaner protect me from malware?
Yes, Combo Cleaner can detect and eliminate most of the known malware infections. However, performing a full system scan is crucial - since sophisticated malicious programs tend to hide deep within systems.
Outstanding!
▼ Show Discussion