Ransomware attacks are one of the most disorienting data loss events a person or business can face. Unlike a drive failure, the data is technically still there — but locked behind encryption. Whether any of it can be recovered, and how, depends heavily on the type of ransomware, what media was affected, and whether the right decisions were made in the first hours after discovery.

What Ransomware Actually Does to Your Storage

Most modern ransomware operates in one of two ways. The first — and most common — is an in-place attack: the malware reads the original file, encrypts the content, and writes the encrypted version back to the same location, typically renaming it with a new extension. The original file is deleted. The second method creates encrypted copies first, then deletes the originals. Both approaches leave the physical storage with no accessible plaintext data, but the behaviour on disk is different and affects what recovery options exist.

Ransomware spreads primarily via phishing emails and malicious downloads, but once inside a network it commonly moves laterally to mapped network drives, NAS devices, and any connected storage it can reach. This is why a single infected workstation can encrypt a business’s entire file server within hours. Strains like LockBit and Black Basta have specifically targeted backup infrastructure to prevent clean restoration without paying the ransom.

Critically, the underlying drive hardware is rarely damaged by a ransomware attack. The platters, NAND cells, and physical media typically remain intact — it is the data layer, not the hardware, that has been compromised. This distinction is important when thinking about what professional recovery services can address.

Can a Data Recovery Lab Decrypt Ransomware Files?

The honest answer is: generally no, not through brute-force decryption. Modern ransomware uses strong encryption algorithms — typically AES-256 or RSA — that are mathematically infeasible to break without the private decryption key. No legitimate data recovery lab will claim to decrypt contemporary ransomware by cracking the encryption itself.

There are, however, situations where recovery is possible without the key. Specialised firms like Ontrack maintain large libraries of custom tools developed for specific ransomware families — in cases where law enforcement has seized encryption keys and released them, or where a particular ransomware strain had implementation flaws in its key generation, decryption without payment may be possible. The No More Ransom initiative (nomoreransom.org), run jointly by Europol and IT security vendors, maintains a free repository of decryption tools for a subset of known strains.

What Labs Can Recover After an Attack

Where data recovery labs provide genuine value in a ransomware incident is in two specific situations. The first is when the ransomware deleted the original files before or after encryption — because the data on a hard drive is not immediately overwritten when a file is “deleted.” The directory entry is removed, but the data sectors are typically still intact until something new is written to them. A recovery lab working quickly, on a powered-down drive, can often retrieve a significant portion of these deleted originals using low-level imaging and carving techniques.

The second is when the ransomware also caused physical or logical drive damage — for example, if a ransomware payload targeted the master boot record, corrupted partition tables, or if the system was running during a power event that coincided with the attack. In these cases, a professional lab addresses the hardware or logical layer first to make the data accessible, after which the encryption question becomes a separate step.

Shadow volume copies (Windows VSS snapshots) are another avenue labs explore — many ransomware strains attempt to delete these, but the deletion is not always complete, and forensic tools can sometimes recover snapshot data that predates the encryption event.

The Role of Backups vs Professional Recovery

The security industry’s consistent guidance is the 3-2-1 rule: three copies of data, on two different media types, with one copy stored offline or off-site. An offline or air-gapped backup cannot be reached by ransomware, no matter how aggressively it propagates across a network. For most businesses and individuals, a good offline backup is a far more reliable recovery path than any post-attack lab engagement.

Professional recovery labs are most useful when the backup strategy failed, was incomplete, or the backup itself was encrypted along with everything else. In these scenarios — which are common, particularly in small businesses that relied on always-connected backup drives — a lab assessment is a rational first step to understand whether any deleted originals can be retrieved before concluding that the data is gone.

Steps to Take Immediately After an Attack

The actions taken in the first hour after discovering a ransomware attack significantly affect the odds of any recovery. The most important is to isolate affected machines immediately by disconnecting them from the network — this limits lateral spread. Do not power off infected servers yet, as some forensic evidence exists only in volatile memory. Identify the ransomware strain by its note and file extension, and check the No More Ransom database before taking any other action.

Do not continue writing to infected drives — every new write reduces the chance of recovering deleted originals. Power down the affected storage after isolation, and image the drives before any restoration attempt begins. If you suspect the attack has also caused physical damage to storage media, or if the drive is not detected at all, contact a professional lab before attempting any software-based recovery.

For professional hard drive and SSD assessment after any data loss event — including ransomware-related drive damage — SouthBit Data Recovery provides a free 24-hour written assessment on a no-fix, no-fee basis. See the pricing page for full detail.

Book a Free Assessment

Sources

• Ontrack — Recover data after ransomware attack without paying ransom
• SentinelOne — Ransomware Data Recovery: Strategies and Best Practices, 2025
• Hornetsecurity — How to Decrypt Files Encrypted by Ransomware, 2025
• No More Ransom — Free decryption tools for known ransomware strains