Question
Clearly sourced
Expert knowledge for digital decisions
How secure is custom-developed software?
Short answer
Neither inherently more secure nor less secure than standard software – it depends on construction and maintenance. Standard software is tested by many, but is also a more lucrative target. Custom software receives less attention, but only gets the attention you pay for.
The Honest Picture
Standard software: many eyes, rapid security updates – but a known vulnerability affects thousands of installations instantly and is automatically exploited.
Custom software: no mass target, no publicly known vulnerabilities – but also no one from outside testing.
The decisive difference lies not in the type of software, but whether it is maintained.
What Contributes to Security
- Current dependencies. The most common cause of successful attacks are known vulnerabilities in outdated libraries.
- Rights and roles. Not everyone needs access to every permission.
- Validate inputs. Protection against classic attacks on web applications.
- Encryption during transmission and for sensitive data.
- Logging. Without logs, no one notices access.
- Backups with verified recovery.
What You Can Request
- Regular updating of dependencies as part of operations
- Automated scanning for known vulnerabilities in the supply chain
- For sensitive applications: external security audit
The Greatest Risk Factor
Not the code – the lack of maintenance. A well-built application that hasn't been updated for two years is vulnerable. That's why a maintenance contract is not an extra service, but a prerequisite.
Key facts
- Decisive Factor
- Whether it is maintained, not whether it is standard or custom
- Most Common Cause of Attacks
- Outdated Dependencies
Sources
All external claims are backed by traceable sources.-
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Cybersecurity Framework (CSF) 2.0 National Institute of Standards and Technology (NIST)
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