A cyber attack — most often ransomware — is one of the most frightening forms of data loss, because it's deliberate, fast, and can hit an entire business at once. Files are encrypted or wiped, a ransom note appears, and panic sets in. But what you do in the first hours after an attack has a huge impact on how much data you recover. This guide covers the data recovery tips that matter most after a cyber attack in 2026: the immediate steps, the mistakes to avoid, and how recovery actually works.
From the engineers at CBL Data Recovery Singapore, who help individuals and businesses recover after attacks.
First, contain the attack
Before recovery, stop the spread. Ransomware and malware often move across networks and connected drives:
- Disconnect affected devices from the network — unplug the ethernet cable or disable Wi-Fi to stop the malware reaching other machines and backups.
- Disconnect external drives and unmount network shares that aren't already encrypted, to protect them.
- Don't shut down abruptly if you can avoid it — for some attacks, a running system holds forensic clues and, occasionally, encryption keys in memory; isolate it from the network instead.
- Identify the scope — which machines, drives and cloud accounts are affected — before acting.
Containment first prevents a bad situation from becoming a catastrophe.
Do not pay the ransom (and why)
It's tempting, but paying a ransom is the wrong move for several reasons: there's no guarantee you'll get a working decryption key, it funds and encourages more attacks, and it marks you as a target for repeat attacks. Law enforcement and security experts consistently advise against paying. Focus your energy on recovery from backups and, where possible, professional decryption or data recovery instead.
How to recover your data after an attack
1. Restore from a clean backup — the best route. If you have an offline or immutable backup that the attack couldn't reach, restoring from it is the fastest, most reliable recovery. This is exactly why an air-gapped backup is so valuable. Wipe the infected systems, confirm they're clean, then restore.
2. Use cloud version history and rollback. If your data was in a cloud service, its version history and account-level rollback (OneDrive Files Restore, Dropbox Rewind) can often revert encrypted files to clean versions from before the attack. See our cloud storage data recovery guide.
3. Check for a free decryptor. For some ransomware families, security researchers have released free decryption tools (initiatives like No More Ransom). Identify the ransomware strain and check whether a legitimate decryptor exists — never download "decryptors" from the attackers or shady sites.
4. Recover deleted or wiped data. Some attacks delete or wipe data rather than encrypt it. In those cases, the data may still be recoverable from the drive, provided it hasn't been overwritten — a job for recovery software or a lab.
5. Consult a professional. For business-critical data, ransomware without a backup, or complex multi-system attacks, professional recovery and incident-response help gives you the best outcome — and avoids mistakes that destroy recoverable data.
Mistakes that destroy recoverable data
After an attack, avoid these:
- Paying the ransom and hoping — often no key, and it invites repeat attacks.
- Running mass "cleanup" or repair tools that overwrite recoverable data.
- Restoring an old backup over the infected system without wiping it first, which can re-infect.
- Reformatting or reinstalling before you've secured any recoverable data.
- Reconnecting to the network before you're sure the threat is removed.
A common mistake is rushing to reformat and reinstall to "start clean" before checking what can be recovered. If files were wiped or deleted (not just encrypted), that data may still be retrievable — but reformatting destroys it. Secure recoverable data first. See our ransomware data recovery service.
How to prevent the next attack
Recovery is the cure; prevention is far better:
- Keep an offline/immutable backup — the single best ransomware defence, following the 3-2-1-1 rule. See our data backup tactics.
- Patch and update systems promptly to close the vulnerabilities attacks exploit.
- Use strong, unique passwords and 2FA, especially on email and remote access.
- Train against phishing — most attacks start with a malicious email or link.
- Limit access and segment networks so an infection can't reach everything.
CBL's ISO-certified lab helps recover data after ransomware and cyber attacks — free diagnosis, fixed quote before any work.
- WhatsApp: +65 8127 7508
- Call: +65 6588 0261
Recovery for individuals vs businesses
The scale and approach differ depending on whether an attack hits a home user or an organisation, and it's worth knowing where you stand.
For individuals, a cyber attack usually means ransomware on a single computer, or a compromised account. Recovery centres on restoring from a personal backup (an external drive or cloud backup), rolling back cloud version history, and checking for a free decryptor. The priority is disconnecting the device, not paying, and recovering personal files — photos, documents — from whatever clean copy exists. If files were wiped rather than encrypted and there's no backup, a lab may recover them from the drive.
For businesses, the stakes and complexity rise sharply. An attack can encrypt servers, shared drives and cloud services simultaneously, halting operations. Business recovery involves incident response (identifying and removing the threat), restoring from immutable or offline backups across many systems, and often reconstructing data from multiple sources. This is where having tested, air-gapped backups and a recovery plan pays for itself many times over — the difference between hours of downtime and a business-ending event. Businesses should also preserve evidence for reporting obligations and, in Singapore, be aware of PDPA breach-notification requirements where personal data is involved.
In both cases, the winning move is the same and it's made before the attack: keep at least one backup the attackers can't reach. Everything about recovery is easier, faster and more certain when a clean copy exists somewhere they never touched.