Ransomware is a type of malware that demands payment by blocking access to files or systems. In some cases, data is extracted before being encrypted and the threat of disclosure is used. Therefore, simply restoring the files may not eliminate all the consequences of the incident.
How can ransomware reach the system?
Phishing attachments, compromised accounts, outdated software, and misconfigured remote access services are possible entry routes. Opening a single file does not explain every event. Especially in businesses, access rights and mobility within the network affect the spread of the event.
For example, a public folder that anyone can write to may allow a single compromised account to access many files. Here, in addition to end-user training, it is also important to narrow sharing permissions and protect backups with separate identities.
Priorities to reduce risk
- Inventory Internet-enabled services; Turn off unnecessary remote access.
- Schedule security updates of the operating system, applications, and network devices.
- Separate admin accounts from daily use accounts and apply MFA.
- Only grant access to shares as needed.
- Keep at least one of the spares separate and protected from the normal operating environment.
- Designate responsible people to monitor logs and endpoint alerts.
First response order in a suspicious incident
If you see mass changes in file extensions, ransom notes, or unexpected access losses, stop processes. In the corporate environment, notify the incident response team or designated contact person. Disconnecting the affected device's network connection in accordance with institutional procedures may limit spread.
- Take note of any symptoms you see, time information, and systems affected.
- Coordinate critical business processes with the responsible team while limiting suspicious system and access.
- Do not delete notes, alerts, and recordings; preserve for review.
- Evaluate whether backups are affected from a separate and reliable environment.
- Verify that the entryway is sealed and the environment is clean before attempting recovery.
Immediately restarting each device or running random cleaning software may lose valuable information for analysis. Decisions such as turning off the device should be made based on the circumstances of the incident and the response plan. Payment of ransom does not guarantee that files will be returned; Do not accept the tools directed by the attacker as reliable.
How to prepare a recovery plan?
First determine which service needs to return and how long it takes. Plan a controlled rollback with clean devices, verified backups, and new access credentials. Investigating whether the infected files have been extracted is also part of the recovery. Update authorization, backup, and remote access controls after the incident.
Frequently asked questions
Is antivirus alone enough?
No. Updates, limited authorization, access security, monitoring and tested backups should be used together.
Will the cloud folder recover my files for sure?
Sync may also move corrupted or encrypted files. Verify version history, retention period, and separate backup capabilities in advance.
Related guides: 3-2-1 backup and incident response steps.
Source and further reading
CISA: #StopRansomware Guide. Source check date: 17 October 2026.
