By the MTP International Quality Engineering Team · October 2026
When a financial institution or healthcare organization suffers a security breach, the regulator doesn’t ask what protection tool was installed. It asks what vulnerabilities existed in the applications, if they had been identified in advance, and what evidence exists that the development team took action to remediate them. This sequence turns software security into a matter of formal compliance, not just technical risk.
Regulated sectors are the most frequent and most affected target. In 2024, the financial sector recorded an average of 1,510 cybersecurity incidents per company per week, a 30% increase from the previous year (Check Point Software Security Report 2025). 60% of hospitals suffered data breaches during the same period. This pressure is not random: it is a direct consequence of the value of the data these sectors process and the attack surface that accelerated digitalization has generated without proportional security validation.
Why Do Regulated Sectors Concentrate the Highest Risk?
The combination of three specific factors explains why banking, fintech, healthcare, and telecommunications concentrate the largest volume of application security incidents:
The data they process has direct and monetizable value: banking credentials, card numbers, clinical histories, identity data. An attacker who compromises a healthcare or financial application obtains assets that can be sold, used for fraud, or leveraged in a ransomware attack.
Regulatory pressure creates a documentation paradox: organizations under CNBV, PCI-DSS, LFPDPPP, or NOM-151 are obligated to demonstrate that their systems are secure, but the speed of software release demanded by the market directly competes with the time needed to validate that security.
Interconnectivity with third parties extends the attack surface beyond proprietary code. APIs connecting banks with fintechs, third-party payment modules on retail platforms, vendor systems in hospitals: each integration is a potential vector that is not always under the control of the internal security team.
The Six Most Critical Vulnerabilities in Regulated Sectors
1. Broken Access Control
This is the most prevalent vulnerability in the OWASP Top 10 2025, found in 94% of tested applications. In regulated sectors, its impact is especially severe because applications manage profiles with radically different privilege levels: a customer, an advisor, a regional administrator, and an auditor should not be able to access the same resources, but in many implementations, simply modifying a URL parameter is enough to escalate privileges or access other users’ records.
For the CNBV and PCI-DSS, the absence of properly implemented access controls is not a minor technical finding: it is a non-compliance that can lead to formal audits.
2. Cryptographic Failures
In OWASP 2025, they rank fourth, but in sectors that process financial or health data, they are a primary risk. The most common failure modes include the use of outdated or weak encryption algorithms, the transmission of sensitive data without encryption on internal channels assumed to be secure, and the storage of credentials or tokens without proper hashing.
PCI-DSS requires specific encryption for card data in transit and at rest. The LFPDPPP mandates protecting personal data with technical controls proportional to its sensitivity. A cryptographic failure in any of these layers is not just a technical risk: it is a regulatory non-compliance with legal consequences.
3. Injections and Cross-Site Scripting (XSS)
SQL, NoSQL, and command injections maintain their position among the three most exploited attack vectors in financial applications. Digital banking applications and healthcare portals are frequent targets because they concentrate high-value data and often have input forms that receive user data without sufficient validation.
XSS allows an attacker to inject malicious code into another user’s browser, which in banking platforms can lead to session hijacking, credential capture, or unauthorized transaction execution. Both categories are detectable with static analysis (SAST) and dynamic analysis (DAST) before reaching production.
4. Software Supply Chain Vulnerabilities
This category is new to the OWASP Top 10 2025 and reflects the impact of incidents like SolarWinds and Log4Shell: vulnerabilities introduced not in proprietary code but in third-party dependencies that the application uses.
Financial sector data is conclusive: 82% of critical security debt in banking, financial services, and insurance organizations comes from vulnerabilities in open-source components with unpatched CVEs (Veracode, State of Software Security 2025). Furthermore, 63% of financial services firms have active critical security debt —high-severity flaws unremediated for more than a year—, a rate 13 percentage points higher than the general average.
5. Authentication and Session Management Failures
Credential stuffing —the automated use of stolen credentials from other breaches to attempt access on new platforms— is one of the most active attacks against digital banking. 48% of fintech companies have been targeted by ransomware, often initiated by compromising an account with weak credentials or sessions without proper expiration.
Controls that mitigate this risk —multi-factor authentication, login attempt limits, inactive session expiration, detection of anomalous location access— must be validated not only in their configuration but also under simulated attack conditions. A control that exists on paper but does not function under real pressure is equivalent to not having it.
6. Inadequately Protected APIs
The OWASP API Security Top 10 documents specific vulnerabilities of programming interfaces: broken object level authorization (BOLA), mass assignment, lack of rate limiting, and server-side request forgery (SSRF). For fintechs and digital banks whose product lives entirely on APIs, these vulnerabilities are the most direct and most frequently undervalued attack vector.
Interconnectivity between financial institutions, data aggregators, and payment platforms through open APIs expands the security perimeter to systems that the organization does not directly control. Each integration is an entry point that must be within the scope of the security testing program.
The Pattern of Security Debt in Finance and Healthcare
What distinguishes regulated sectors is not just the type of vulnerabilities they have, but the speed at which security debt accumulates without being remediated. 63% of financial firms have high-severity flaws uncorrected for more than a year. This means that vulnerabilities are known but not prioritized, often because the development team lacks a structured process to convert security findings into sprint tasks with clear acceptance criteria.
Remediation without a process produces the same cycle: the pentest identifies findings, the security team produces a report, the report goes into a work queue where it competes with the backlog of new functionalities, and high-severity findings remain open for months as the next audit cycle approaches.
MTP’s Perspective
At MTP, we integrate security validation as a continuous layer of the QE pipeline, not as a one-time exercise before an audit. With Omniatest®, our proprietary methodology —MTP is the first TMMi Level 5 certified company in the world—, security quality gates block pipeline progression when high-criticality findings are detected, and each finding produces auditable evidence that the regulator can review.
Working with financial and healthcare organizations in Mexico has shown us that the relevant question is not whether vulnerabilities exist: they always do. The question is whether there is a process to find them before an attacker does, remediate them with correct priority, and document the evidence the regulator will request.
Frequently Asked Questions
- Is the OWASP Top 10 sufficient as a security framework for a regulated organization in Mexico? The OWASP Top 10 is a solid and widely recognized starting point: regulatory frameworks such as ISO 27001, SOC 2, and PCI-DSS explicitly cite it as a standard for secure coding. In Mexico, the CNBV and the LFPDPPP do not mention it by name in their circulars, but the coverage of its categories is accepted evidence of secure development practices during audits. That said, the OWASP Top 10 covers vulnerabilities in web applications; a regulated organization also needs to cover APIs (OWASP API Top 10), mobile (OWASP Mobile Top 10), and cloud infrastructure, depending on its stack.
- What is the difference between security debt and an active vulnerability? An active vulnerability is a confirmed security flaw that exists in the system and can be exploited by an attacker. Security debt is the set of known vulnerabilities that the team decided not to remediate immediately —due to priority, resources, or correction cost— and that remain open. The problem with security debt is that it silently accumulates risk: a high-severity flaw open for more than a year is not just a technical risk, it is a regulatory non-compliance in any organization under PCI-DSS or CNBV supervision.
- How often should security tests be run on banking or healthcare applications? In organizations with frequent release cycles —weekly or bi-weekly— static analysis (SAST) should be executed in each integration cycle as an automatic quality gate. Dynamic analysis (DAST) should be executed on staging environments for each significant release. Manual penetration testing, which simulates a real attack performed by a specialist, should be conducted at least once a year as a complete validation of the security posture, and always before high-impact architectural changes: cloud migration, incorporation of new APIs, launch of a new digital channel.
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