"We consider Citadelo to be a trustworthy partner in developing both the process and technical aspects of information security. We appreciate their expertise, professional approach, and the results of their work."
TrustPay a.s.
Ivan Poliačik
Cybersecurity for Financial Services
Cybersecurity for Financial Services
Security Testing for the Financial Sector
We assess the security of banking and payment systems, applications, APIs, cloud environments, and internal infrastructure. Testing focuses on protecting financial data, customer accounts, transactions, and critical services. We help uncover vulnerabilities that could lead to unauthorized payments, data breaches, account takeover, or service outages. The scope is tailored to your technologies, risks, and financial-sector regulatory requirements.
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Helping Organizations Reduce Cyber Risk
3,000+ projects
We have completed more than 3,000 cybersecurity projects.
14 years
More than 14 years of experience in ethical hacking.
47 experts
A team of 47 certified experts.
20+ CVEs
Our experts have discovered more than 20 officially registered vulnerabilities.
3,293 findings
Security findings identified in 2025.
Why Test the Security of Financial Services?
Financial organizations process sensitive personal data, execute payments, and operate services that must remain continuously available. A successful attack can lead to unauthorized transactions, customer account takeover, data breaches, or widespread service disruption.
Banking systems, mobile applications, APIs, cloud services, and external suppliers create an interconnected environment with multiple potential attack paths. A vulnerability in a single component can allow an attacker to reach other systems or bypass existing security controls.
Security testing helps uncover these weaknesses before real attackers exploit them. It also provides practical evidence for risk management and verification of technical security measures.
Protection of Customer Data
We assess systems that process customers’ personal, financial, and authentication data.
More Secure Transactions
We examine opportunities to manipulate payments, abuse accounts, or bypass authorization mechanisms.
Availability of Critical Services
We identify weaknesses that could disrupt online banking, payment systems, or other financial services.
Better Risk Visibility
Each finding is evaluated according to its technical severity and potential financial, operational, and regulatory impact.
Trusted by Financial Organizations
"Citadelo's expertise is backed by the experience we've gained through our joint projects. Their professionalism and flexibility in identifying vulnerabilities within the paperless insurance environment are essential to us. Our mutual trust is built on their strong ethical standards and unwavering reliability in protecting our clients' sensitive data. They are a partner that keeps pace with the realities of today's cyber threats.!
YOUPLUS Životná poisťovňa
Vlastimil Šmihula | CIO
“In banking, simply testing a web application and delivering a report isn't enough. Citadelo understands that our security needs extend from APIs and customer portals all the way to ATMs. What we value most is the breadth of their technical expertise. Their ability to adapt to our systems, combined with clear, actionable findings, makes them a trusted partner in protecting what matters most – our customers' data and money.”
Slovenská sporiteľňa
Ján Adamovský | Chief Security Officer v SLSP
"Our collaboration in the field of information security is long-term. During this period, I have repeatedly been convinced of both their professional and personal qualities."
PENTA INVESTMENTS LIMITED o. z.
Michal Prónay | Head of IT
"The penetration testing report provided us with an objective view of the security of our applications. We were satisfied with the terms and the execution of the service."
Union zdravotná poisťovňa, a. s.
Martin Spišák | Head of IT
Who Is Security Testing For?
We tailor testing to the type of financial organization, technologies used, data processed, and applicable regulatory obligations.
Banks and Credit Institutions
We assess online and mobile banking, payment systems, APIs, internal infrastructure, and processes related to customer account management.
Insurance and Investment Companies
We test customer portals, applications, contract and investment management systems, and the protection of personal and financial data.
FinTech and Payment Companies
We assess the security of digital payments, mobile applications, payment gateways, APIs, and services connected to banks or external providers.
Cryptocurrency and Blockchain Projects
We test cryptocurrency platforms, exchanges, wallets, smart contracts, and related applications, focusing on the protection of accounts, assets, and transactions.
What Do We Test in Financial Organizations?
Online and Mobile Banking
Through web application penetration testing and mobile application penetration testing, we assess authentication, account management, transaction authorization, data protection, and resilience against abuse.
Payment Systems and Transactions
We test payment processing, payment gateways, transaction verification, and protection against unauthorized manipulation.
APIs and Open Banking
Through API penetration testing, we assess authorization, data access, request validation, and the security of interfaces connecting banks, partners, and external services. Explore the most common web application and API vulnerabilities identified during real-world testing.
Customer Portals and Web Applications
We look for vulnerabilities that could lead to account takeover, data leakage, privilege escalation, or abuse of business logic.
Cloud and Internal Infrastructure
Through cloud penetration testing and network infrastructure penetration testing, we assess configurations, segmentation, servers, databases, Active Directory, and opportunities for lateral movement. Learn why our project data shows that cloud environments have the highest number of vulnerabilities per test.
Identity and Access Management
We test authentication, multi-factor authentication, user roles, privileged accounts, and access permission management.
Suppliers and External Integrations
We assess risks associated with supplier access, external platforms, payment services, and other integrations.
Employees and Internal Processes
Through social engineering testing, we assess employees’ resilience to phishing, vishing, and other manipulation attempts.
Security Testing and Regulatory Requirements
Financial organizations must be able to demonstrate that they regularly assess their systems, manage information technology risks, and verify that implemented security measures work in practice. Regulatory frameworks emphasize the protection of sensitive data, availability of critical services, third-party risk management, and preparedness for cyber incidents. We therefore tailor the testing scope to your organization’s technologies, risks, and obligations. The results help identify weaknesses, prioritize remediation, and demonstrate regular security verification.
Security testing does not replace legal assessment or a comprehensive compliance audit. Audits and penetration tests answer different questions and complement each other when properly designed. We explain the distinction in our article Security Audit vs. Penetration Testing.
Discuss your testing requirements
Relevant Regulatory and Security Frameworks
DORA
DORA requires financial entities to establish a digital operational resilience testing program. Penetration tests, vulnerability assessments, and other forms of security testing help identify weaknesses and verify the effectiveness of protective measures.
TIBER-EU and TLPT
Advanced threat-led testing may be relevant for selected financial entities. Red Teaming based on the TIBER-EU framework assesses technologies, employees, and processes through a controlled and realistic attack scenario. The updated TIBER-EU framework is aligned with DORA requirements for TLPT.
PCI DSS
For organizations that store, process, or transmit payment card data, testing helps verify the security of the cardholder data environment and identify potential attack paths to sensitive payment information.
NIS2
For organizations subject to the sector-specific DORA regulation, DORA acts as a specialized legal framework in several areas. Specific obligations nevertheless depend on the type of entity, the services it provides, and applicable legislation.
Red Teaming for Financial Organizations
Red Teaming assesses technologies, employees, and internal processes through a realistic attack scenario. For selected financial entities, it can also support testing related to DORA requirements for TLPT and the TIBER-EU framework.
Learn more about Red Teaming
How Can an Attack Affect a Financial Organization?
Attackers often combine weaknesses in applications, identities, APIs, and internal infrastructure. Testing therefore examines not only individual vulnerabilities but also their potential consequences.
Customer Account Takeover
Weaknesses in authentication, password recovery, or multi-factor authentication can allow an attacker to gain control of a customer’s account.
Transaction Manipulation
Authorization and business logic flaws can enable unauthorized changes to the amount, recipient, or other payment parameters.
Compromise Through an API or Supplier
A vulnerable interface, external integration, or compromised supplier account can provide a path to financial data and internal systems.
Exploitation of Employees
Phishing, vishing, or a convincing pretext can help an attacker obtain credentials or trigger an unauthorized payment.
Disruption of Critical Services
An attack against applications or infrastructure can affect the availability of online banking, payment systems, and other financial services.
Explore Other Options
Industry-Specific Cybersecurity
See how we tailor security testing to the technologies, risks, operating conditions, and regulatory requirements of organizations across different industries.
Explore tested industries
Penetration Testing
Through realistic attack simulations, we assess web and mobile applications, APIs, cloud environments, internal infrastructure, AI systems, and other technologies.
Learn more about penetration testing
Red Teaming
Through a comprehensive attack scenario, we assess the resilience of technologies, employees, and internal processes, as well as the security team’s ability to detect, stop, and manage an attack.
Learn more about Red Teaming
The Citadelo team holds dozens of certifications, including OSCP, OSWE, OSEP, CRTO, CRTE, and CISSP, relevant to testing financial applications, systems, and infrastructure.
Experienced Ethical Hackers Protecting Financial Systems
We use our experience from penetration testing and Red Teaming to create realistic scenarios. We verify vulnerabilities without unnecessarily putting customers, transactions, or operations at risk.
Book a free consultation
Frequently Asked Questions
Answers to common questions about security testing for banks, insurance companies, FinTech businesses, and other financial organizations.
We test online and mobile banking, payment systems, customer portals, APIs, cloud environments, internal infrastructure, identities, and external integrations. The scope is tailored to the technologies used and the organization’s most significant risks.
Yes. Before testing begins, we define the scope, safety boundaries, schedule, and procedure for handling critical findings. Higher-risk scenarios are performed only by agreement or in a separate testing environment.
We plan testing to minimize its impact on transactions, customers, and service availability. Potentially risky steps are discussed in advance and are not performed in production without explicit approval.
Testing can provide technical evidence for a digital operational resilience testing program and verify the effectiveness of implemented measures. However, it does not replace legal assessment or a comprehensive DORA compliance audit.
We perform Red Teaming and advanced testing based on current threats. The possibility of conducting TLPT is assessed according to DORA requirements, the TIBER-EU framework, the scope of critical functions, and the requirements of the relevant authority.
Yes. We can tailor the scope to the cardholder data environment and PCI DSS requirements. We assess systems, applications, network segmentation, and potential attack paths to payment card data. Testing alone, however, does not replace a comprehensive compliance assessment.
Yes. We test supplier access, external platforms, APIs, payment services, and other integrations. We assess whether their compromise could provide an attacker with access to financial data or internal systems.
Before testing begins, we define rules for accessing, processing, storing, and transferring sensitive data. We work only with data necessary for testing and deliver all findings through agreed secure channels.
You will receive a technical report describing the vulnerabilities, supporting evidence, risk ratings, and specific remediation recommendations. The deliverables may also include an executive summary and a results consultation with our ethical hackers.
Yes, a retest can be included in the agreed project scope. Once remediation is complete, we verify whether the vulnerabilities have been properly resolved and whether the changes introduced any additional security risks.
Would You Like to Assess the Security of Your Financial Systems?
Book a free 15-minute consultation. Together, we will define an appropriate testing scope based on your technologies, most significant risks, and regulatory requirements.
Book a free consultation
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