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	"title": "Fog",
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	"plain_text": "Fog\r\nBy SentinelOne\r\nPublished: 2024-08-08 · Archived: 2026-04-06 00:54:35 UTC\r\nFog Ransomware: In-Depth Analysis, Detection, and Mitigation\r\nWhat Is Fog Ransomware?\r\nFog Ransomware emerged in April of 2024 with operations targeting both Windows and Linux endpoints. Fog is a\r\nmulti-pronged extortion operation, leveraging a TOR-based DLS to list victims and host data for those that refuse\r\nto comply with their ransom demands.\r\nWhat Does Fog Ransomware Target?\r\nFog ransomware targeting has been primarily focused on education, recreation and travel, and manufacturing\r\nsectors. Targeting is mainly on United States entities, though there is nothing to indicate they would not target\r\nentities outside of the United States.\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 1 of 8\n\nHow Does Fog Ransomware Work?\r\nFog threat actors rely heavily on exploitation of known-vulnerable applications. Operators typically achieved\r\ninitial access via the purchase of compromised credentials from an Initial Access Broker (IAB). Operators will\r\nleverage the purchased accounts to establish a foothold in the environment then move laterally in a methodical\r\nway.\r\nFog ransomware variants exist for both Windows and Linux platforms. The Linux-flavored variants include\r\nspecific targeting tuned for virtual environments (e.g., VMSD and VMDK files). The Fog payloads will also make\r\nattempts to terminate various processes associated with these virtualized environments.\r\nFog Ransomware supports multiple command-line parameters. These include:\r\nCommand-Line Parameters Description\r\n–help display all available syntax\r\n–offvm force termination of VM-related processes\r\n–size file encryption percentage (e.g., 70%)\r\n–target path/directory to encrypt\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 2 of 8\n\n–id ID/password to execute (required)\r\n–fork without terminal, daemon mode\r\n–log (file) switch on log to terminal and file, if file not set then defaults to terminal\r\n–nomutex do not check for existing running processes\r\n–showtalkid show talkid (campaign ID) and exit – no encryption\r\n–processallfiles ignore hard coded extension configuration and encode all files on disk\r\n–thread use N threads (resource management)\r\nUpon encryption, the extensions .fog, .Fog or .FLOCKED are appended to the affected files.\r\nWindows-based variants of Fog ransomware will attempt to delete volume shadow copies via vssadmin.exe.\r\nVssadmin.exe delete shadows / all /quiet\r\nAdditionally, the Windows versions of Fog include a JSON-based configuration section. Operators are able to\r\ncustomize the extension appended to encrypted files along with configuration of the ransom note name,\r\nprocess/service termination and the RSA public key to be embedded for encryption use.\r\nFog ransom notes are written to each location containing encrypted files as “readme.txt”. The note instructs\r\nvictims to communicate with the attackers via their TOR-based victim portal.\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 3 of 8\n\nThe Fog ransomware DLS was first observed in July 2024 and is available via TOR only with no clearnet mirrors\r\nas of this writing.\r\nHow to Detect Fog Ransomware\r\nThe SentinelOne Singularity XDR Platform can identify and stop any malicious activities and items related to Fog\r\nransomware.\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 4 of 8\n\nEtt fel inträffade.\r\nDet går inte att köra JavaScript.\r\nIn case you do not have SentinelOne deployed, detecting Fog ransomware requires a combination of technical and\r\noperational measures designed to identify and flag suspicious activity on the network. This allows the organization\r\nto take appropriate action, and to prevent or mitigate the impact of the ransomware attack.\r\nTo detect Fog ransomware without SentinelOne deployed, it is important to take a multi-layered approach, which\r\nincludes the following steps:\r\n1. Use anti-malware software or other security tools capable of detecting and blocking known ransomware\r\nvariants. These tools may use signatures, heuristics, or machine learning algorithms, to identify and block\r\nsuspicious files or activities.\r\n2. Monitor network traffic and look for indicators of compromise, such as unusual network traffic patterns or\r\ncommunication with known command-and-control servers.\r\n3. Conduct regular security audits and assessments to identify network and system vulnerabilities and ensure\r\nthat all security controls are in place and functioning properly.\r\n4. Educate and train employees on cybersecurity best practices, including identifying and reporting suspicious\r\nemails or other threats.\r\n5. Implement a robust backup and recovery plan to ensure that the organization has a copy of its data and can\r\nrestore it in case of an attack.\r\nHow to Mitigate Fog Ransomware\r\nThe SentinelOne Singularity XDR Platform can return systems to their original state using either the Quarantine\r\nor Repair.\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 5 of 8\n\nEtt fel inträffade.\r\nDet går inte att köra JavaScript.\r\nIn case you do not have SentinelOne deployed, there are several steps that organizations can take to mitigate the\r\nrisk of Fog ransomware attacks:\r\n1. Educate employees: Employees should be educated on the risks of ransomware, and on how to identify\r\nand avoid phishing emails, malicious attachments, and other threats. They should be encouraged to report\r\nsuspicious emails or attachments, and to avoid opening them, or clicking on links or buttons in them.\r\n2. Implement strong passwords: Organizations should implement strong, unique passwords for all user\r\naccounts, and should regularly update and rotate these passwords. Passwords should be at least 8 characters\r\nlong, and should include a combination of uppercase and lowercase letters, numbers, and special\r\ncharacters.\r\n3. Enable multi-factor authentication: Organizations should enable multi-factor authentication (MFA) for\r\nall user accounts, to provide an additional layer of security. This can be done through the use of mobile\r\napps, such as Google Authenticator or Microsoft Authenticator, or through the use of physical tokens or\r\nsmart cards.\r\n4. Update and patch systems: Organizations should regularly update and patch their systems, to fix any\r\nknown vulnerabilities, and to prevent attackers from exploiting them. This includes updating the operating\r\nsystem, applications, and firmware on all devices, as well as disabling any unnecessary or unused services\r\nor protocols.\r\n5. Implement backup and disaster recovery: Organizations should implement regular backup and disaster\r\nrecovery (BDR) processes, to ensure that they can recover from ransomware attacks, or other disasters.\r\nThis includes creating regular backups of all data and systems, and storing these backups in a secure,\r\noffsite location. The backups should be tested regularly, to ensure that they are working, and that they can\r\nbe restored quickly and easily.\r\nFog Ransomware FAQs\r\nWhat is Fog ransomware?\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 6 of 8\n\nFog ransomware is a malicious file encryptor that targets organisational data and demands payment for\r\ndecryption. It was discovered in recent years and spreads through various infection vectors. The ransomware\r\nencrypts your documents, databases, and media files. After encryption completes, you’ll receive a ransom note\r\nwith payment instructions.\r\nWhich sectors are primarily targeted by Fog ransomware?\r\nFog ransomware mainly targets the healthcare, education, and manufacturing sectors. It will focus on\r\norganisations with valuable data and poor security practices. Small businesses are frequent targets because they\r\noften lack robust protections. If you operate in these industries, you should strengthen your security posture\r\nimmediately. Government agencies have also reported Fog infections.\r\nHow does Fog ransomware operate?\r\nFog ransomware enters systems through phishing emails and vulnerable remote connections. It first establishes\r\npersistence mechanisms and disables security tools. The ransomware then scans for valuable files across local and\r\nnetwork drives. It tries to stop recovery options by deleting shadow copies. You’ll see it encrypt your files and\r\nleave ransom notes before demanding payment.\r\nWhat file extensions does Fog ransomware append to encrypted files?\r\nFog ransomware adds the “.fog” or “.foggy” extension to encrypted files. It will modify your filenames to include\r\na unique victim identifier. For example, “document.docx” becomes “document.docx.fog” after encryption. You\r\ncan quickly identify affected files by looking for these extensions. The ransomware targets over 200 file types,\r\nincluding documents, images, and databases.\r\nWhat commands does Fog ransomware execute upon infection?\r\nFog ransomware runs commands to disable Windows Defender and other security tools. It will delete shadow\r\ncopies using “vssadmin delete shadows /all /quiet”. The malware stops database services from encrypting database\r\nfiles properly. You’ll find it using PowerShell to turn off security features. It creates scheduled tasks for\r\npersistence and modifies registry settings to maintain access.\r\nWhat are the indicators of compromise (IOCs) for Fog ransomware?\r\nYou can identify Fog ransomware by files with “.fog” extensions and ransom notes called\r\n“HOW_TO_RECOVER.txt”. The ransomware creates specific registry keys and scheduled tasks. It will establish\r\nconnections to command servers. You should look for stopped security services and deleted backup files. You’ll\r\nnotice suspicious PowerShell commands and privilege escalation attempts if you check system logs.\r\nHow can organisations detect a Fog ransomware infection?\r\nOrganisations can detect Fog using SentinelOne’s Singularity XDR platform. If you don’t have that deployed,\r\nmonitor for mass file modifications and suspicious network traffic. You should set up alerts for known Fog\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 7 of 8\n\nbehaviors like shadow copy deletion. Look for unusual account activities and privilege escalation attempts.\r\nRegular security scans can help identify Fog components before activation.\r\nWhat preventive measures can help protect against Fog ransomware?\r\nYou should implement email filtering and anti-phishing solutions, keep all systems patched and updated, and train\r\nyour employees to recognise suspicious emails and attachments. Network segmentation can limit ransomware’s\r\nspread. Make regular offline backups of critical data. You can also deploy application allowlisting and least\r\nprivilege access controls.\r\nAre endpoint detection and response (EDR) tools effective against Fog ransomware?\r\nYes, EDR tools like SentinelOne can effectively detect and block Fog ransomware. They monitor system\r\nbehaviors and identify suspicious activities in real time. You should deploy EDR across all endpoints. These tools\r\ncan stop the ransomware before encryption completes. If you fail to use EDR, you risk complete system\r\ncompromise and data loss.\r\nWhat steps should be taken immediately after a Fog ransomware infection?\r\nIf infected by Fog, disconnect affected systems from the network immediately. If possible, don’t pay the ransom.\r\nReport the incident to authorities like CISA and the FBI. If available, restore your data from clean backups. Before\r\nreconnecting systems, scan for remaining malware and patch all vulnerabilities. You can perform forensic analysis\r\nto determine how the attackers got in.\r\nSource: https://www.sentinelone.com/anthology/fog/\r\nhttps://www.sentinelone.com/anthology/fog/\r\nPage 8 of 8",
	"extraction_quality": 1,
	"language": "EN",
	"sources": [
		"Malpedia"
	],
	"references": [
		"https://www.sentinelone.com/anthology/fog/"
	],
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		"fog"
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