System hardening and vulnerability remediation in Corsica
System hardening means reducing the ways into your IT by removing what you do not need, fixing vulnerabilities and applying safer settings. From Bastia, we secure your computers, servers, networks, applications and data, and check that every fix holds without disrupting your business.
Hardening and remediation: two steps to secure your IT
Hardening starts from a simple principle: every service switched on, every open account and every installed program is a potential door. Hardening a system means closing the doors you do not need, locking the ones that must stay open and applying stricter settings than the factory defaults.
Remediation means fixing vulnerabilities that have already been identified by an audit, a penetration test or a security alert. It may involve applying an update, changing a configuration, reviewing access rights or, where no fix exists yet, putting a temporary safeguard in place.
The two go hand in hand: remediation deals with known flaws, while hardening reduces the chance of new ones appearing.
When should you start vulnerability remediation?
- 01
After an audit or penetration test
You have a report and a list of vulnerabilities: now they need fixing in the right order, and checking to confirm they are closed.
- 02
When installing a new system
A new server, network or website is far easier to secure before it goes into service than once it is live.
- 03
When a published flaw affects you
A vulnerability is announced in software you use: you need to check whether you are exposed and act quickly.
- 04
After an incident
Once operations are restored, hardening the affected systems reduces the risk of a similar incident.
What system hardening covers in practice
- 01
Accounts and access
Two-factor authentication, strong passwords kept in a password manager, removal of unused accounts, admin rights limited to those who need them.
- 02
Updates
Operating systems, software, website plug-ins and network devices kept up to date, with a method so that nothing gets forgotten.
- 03
Network
A better-configured firewall, guest Wi-Fi separated from the internal network, secure remote access.
- 04
Servers and websites
Unnecessary services disabled, encrypted connections and protected admin interfaces, following OWASP and ANSSI recommendations.
- 05
Email
Settings that make it harder for anyone to impersonate your domain name in fake emails.
- 06
Data and backups
Encryption of sensitive data, backups isolated from the network and restores that are actually tested.
Securing your IT: priorities by sector
- 01
Shops and trades
Email, the till and backups first, to avoid downtime and payment fraud.
- 02
Hospitality and tourism
Strict separation between guest Wi-Fi and management tools, and a secure booking website.
- 03
Practices and healthcare
Encrypted computers and files, named user accounts, a record of who accessed what.
- 04
Startups
Cloud infrastructure, developer access and the protection of secrets such as service access keys.
- 05
Public bodies
Staff accounts, shared computers and public portals, with particular attention to continuity of service.
How a hardening engagement unfolds
All work is carried out with your written agreement, on systems you are responsible for, and according to a plan agreed together.
- 01
Understand
We start from your audit or test report, or from a quick review if you do not have one.
- 02
Prioritise
Fixes are ranked by risk, effort and impact on your business. The most urgent come first.
- 03
Plan
Each change is prepared with a prior backup and a rollback plan, then scheduled in an agreed time window.
- 04
Apply and verify
We apply the changes, check that everything still works and confirm that the vulnerability is closed.
- 05
Document
Every setting is recorded, so that you or your provider can maintain it.
Deliverables, verification and follow-up
- 01
A change log
What was changed, when, why, and how to roll it back if needed.
- 02
Configuration documentation
The settings chosen for your systems, reusable for any new device.
- 03
Vulnerability status
For each vulnerability in the original report: fixed, mitigated or accepted in full knowledge of the risk.
- 04
Simple guidelines
A few practical rules for your team, such as using two-factor authentication or what to do with a suspicious message.
- 05
Follow-up
After the engagement, we can keep track of updates and run periodic reviews, or train your team to take over.
Points to watch and remediation cost factors
Poorly prepared hardening can block business software or stop someone from working. That is why we test every change and always plan a way back. As for budget, the quote depends mainly on the following.
- 01
Number of vulnerabilities and systems
The computers, servers, websites and devices involved.
- 02
Age of your equipment
Systems that no longer receive updates call for workarounds, or even replacement.
- 03
Business constraints
Work outside opening hours or out of season, a test environment to set up.
- 04
Business software
Whether it copes with stricter settings, which sometimes needs checking with its vendor.
- 05
Level of follow-up
A one-off intervention or ongoing support.
Technologies and methods
- System hardening
- Patch management
- Two-factor authentication
- Firewall and segmentation
- Backups
- ANSSI recommendations
Frequently asked questions
Can you fix vulnerabilities found by another provider?
Yes. We start from their report, verify each finding, then fix according to the priorities agreed with you. A final retest confirms that the vulnerabilities are closed.
Will hardening make our team's work harder?
Some changes are unavoidable, two-factor authentication for example. We always aim for a level of security that remains workable day to day, and we support your team through the transition.
What if a piece of software can no longer be updated?
We isolate it as far as possible from the rest of the network and from the internet, restrict access to it and help you plan its replacement.
Do you work on site?
Yes, in Corsica, when the work requires it. Many settings can also be changed remotely, through temporary access that you open and close yourself.
Once hardened, are our systems protected for good?
No. New vulnerabilities are discovered all the time and your tools keep changing. Hardening needs maintaining, through tracked updates and regular reviews.