SQL BACKUP BAK Format
Is your SQL backup in BAK format encrypted after a ransomware attack?
Even when a SQL Server backup in BAK format can no longer be restored following a ransomware attack, SOS RANSOMWARE steps in to analyze, reconstruct, and recover your company's priority data. Our R&D engineers use advanced analysis methods to identify recoverable data blocks, reconstruct damaged SQL structures, and restore the critical databases required to resume business operations.
Client Case: SME Based in Paris, France
Discover how SOS RANSOMWARE recovered priority data from a SQL backup in BAK format that had become unusable following a ransomware attack.
An SME based in Paris, France, contacted us through SOS RANSOMWARE after a ransomware attack made a SQL Server backup impossible to restore.
The affected backup was a 15 GB .bak file containing a critical database:
PHARMA_20250714.bak
Following the ransomware attack, the file had been renamed with a suffix added by the ransomware:
PHARMA_20250714.bak.lockbit3
Total volume analyzed: 15 GB
Client objective: recover the priority SQL data contained in this backup to enable the company to quickly resume operations.
Secure Transfer of the SQL BAK Backup
From the very first contact, our specialists carry out a comprehensive assessment of the situation in order to:
- Identify the source of the problem.
- Assess the actual condition of the SQL backup.
- Determine the technical recovery options.
- Identify the priority data required by the company.
To facilitate the transfer of the backup, our team set up a unique and secure FTP link, allowing the client to send the entire affected SQL backup file in BAK format.
Once the complete backup had been received, our engineers carried out an initial technical analysis to assess its condition.
Standard SQL BAK Backup Restoration Impossible
An initial attempt was made to open the SQL BAK backup using standard SQL Server restoration methods.
The software returned an error message confirming that the backup could no longer be used with conventional restoration procedures.
The database was considered unusable by standard SQL restoration tools.
Advanced Technical Analysis and Reconstruction of the SQL Database in BAK Format
As standard recovery methods could not be used, the analysis was entrusted to our R&D engineering team specializing in post-ransomware data recovery.
The initial checks revealed that:
- Approximately 21% of the analyzed segments contained incomplete structures or unreadable data blocks.
- Some internal blocks within the backup nevertheless remained recoverable.
- A partial reconstruction of the SQL database could be initiated.
Our engineers then performed a complete mapping of the BAK file to isolate the data blocks that were still readable.
An initial extraction of the recoverable elements produced preliminary results. A technical discussion with the client then helped assess the possibilities for improving the recovery rate.
In this case, the Paris-based company was unfortunately unable to provide an additional data source to support the analysis.
Despite this limitation, an in-depth analysis of the SQL BAK file, combined with the use of specialized tools developed by SOS RANSOMWARE, produced significant recovery results.
Results Achieved: 95% of Priority Files Recovered
After reconstructing the recoverable structures, the following results were confirmed with the client:
Recovery Results
- Initial volume analyzed: 15 GB
- Recoverable volume reconstructed: 12 GB
- Overall recovery rate: 63%
- Priority files recovered: 95%
- Client validation: 100%
Despite the ransomware encryption that had rendered the SQL BAK backup unusable, the priority data was successfully recovered and validated.
Validation of Recovered SQL BAK Data
To ensure reliable validation before data return, the recovered database files were mounted on a secure SQL server made available to the client.
This step allowed the company to:
- Review the restored database.
- Verify the contents of the tables.
- Check the priority data.
- Validate the results before final delivery.
For File Server data present in the recovered environment, secure access to DiagView was also provided to facilitate file review.
Data Delivered Within 48 Hours
After final validation via the secure SQL server and the DiagView environment:
- The recovered data was transferred via secure FTP.
- The data was returned according to the agreed procedure.
- The data was delivered within 48 hours.
This intervention enabled the Paris-based company to quickly regain access to its critical data and limit the operational impact of the ransomware attack.
Our Recovery Process for SQL BAK Backups
Contact & Qualification Call
Advanced Diagnosis
Fixed Quote
Recovery
File Listing & Validation
Secure Data Return
Why Choose SOS RANSOMWARE to Recover Your SQL BAK Backup?
With over 250 ransomware cases handled, we have adapted our tools and processes to achieve successful recovery results.
Since 2019, we have been developing tools specifically designed for post-ransomware data recovery.
Our emergency response team is available 24/7. Our software and servers are regularly updated to speed up our recovery process.
We offer a free analysis of a file of your choice (VM, backup, or database) to demonstrate our expertise. Simply send it to us.
How quickly do you need your data back?
We offer flexible service options to meet your specific needs and budget requirements.
On-call service
24/7/365
Dedicated team
Average turnaround time: 1–3 business days
Priority processing during business hours
1 dedicated engineer
Average turnaround time: 3–7 business days
Processing during business hours
1 shared engineer
Average turnaround time: 7–14 business days
Témoignages
Success stories
Une sauvegarde ACRONIS cryptée par un ransomware
Un agent immobilier nous contacte après avoir été crypté par un groupe de ransomware.
Ils nous fournissent donc un fichier .TIB de 4 TO.
Nous constations que le chiffrement a touché tous les débuts de fichiers à hauteur de 8 Go.
Heureusement, ils ont coupé le NAS au début de l’attaque. Il ont retiré le disque système du NAS. 4 répertoires seulement sont manquants. Une société de récupération de données fera donc des recherches de fichiers supprimés mais tous fichiers retrouvés sont corrompus.
Nous analysons donc la structure et la compression des fichiers.
Nous avons pu récupérer 95 % des données sur ce dossier.
Une sauvegarde TIBX échoue en raison d'une erreur d'E/S.
Le prestataire IT nous envoie un disque dur qui contient des fichiers de sauvegardes TIBX. Le logiciel indique une erreur “Data error (cyclic redundancy check)” .
Ce message d’erreur indiqu’il y a des erreurs physique sur le disque. Nous procédons donc à un clonage du disque. Le fichier SPF ne fonctionne pas. Il y a des erreurs : il est corrompu.
Nous récupérons plus de 90 % des données malgré les erreurs.
Request an Evaluation
Once we receive your request, we will arrange a technical call with our engineers.
FAQ
Frequently Asked Questions
Everything you need to know about database data recovery services.
Database data recovery is a technical process used to restore information stored in a database or backup that has become inaccessible, corrupted, or damaged.
Following a ransomware attack, this process involves analyzing the internal data structures to identify recoverable elements, reconstruct files, and restore the priority information required for business continuity.
Yes. Even when a SQL Server BAK file can no longer be restored using standard tools, our engineers analyze its internal structure to identify recoverable data blocks and reconstruct the data that can be recovered.
We recommend contacting our team as soon as possible after discovering a ransomware attack to maximize the chances of successful recovery.
A technical analysis allows us to assess the condition of the BAK file and determine an appropriate recovery strategy.