Risky algorithms, Accessing freed memory, Forgotten resource limits, Buffer overflow, Type overflow, Undeclared functions are common programming errors. Neither a beginner nor an experienced programmer is immune from errors. This list will help you avoid the most common ones.

1. Working with undeclared variables

You exert a variable that was not specified in the variable declaration block and did not receive its own type. How the program will react to this depends on the selected language.

Check all the variables, make sure you declare them and apply some additional style enhancement options. For example, commentaries.

2. Initializing variables with no initial value

It is not enough to declare variables and Programming errors, you need to keep track of their initial values. In most languages, before you put something into the allocated memory area, residual garbage will be stored there, that is any binary code that remained in the cells before the program started. This leads to unpleasant incidents.

3. Undeclared functions

This error is especially common when using ready-made functions stored in separate files or libraries. No compiler will miss a bug like this. But finding the reason for the constant “crash” on a line with a function often takes a lot of time.

4. Type overflow

Sometimes it happens that the code looks logical, and the program crashes by mistake of Programming errors due to problems with the allocation of memory for a particular type of variable.

Avoiding this is simple: do not forget to add a check for values for the maximum allowed, or just use devops services by DataArt.

5. Buffer overflow

Some modern languages are protected from this vulnerability, and therefore, as a result of an overflow, the program simply crashes by mistake. Others are still susceptible to such a bug, as a result, the user gets “holes” in the protection of the computer, through which malicious code can penetrate.

6. Errors in estimating array bounds

In fact, access to a nonexistent array element is possible not only in C and C++, but also in Python, Java, and many other languages. The essence of the problem(Programming errors) lies in the fact that the programmer refers to an array element with a non-existent number.

To avoid problems, do not be too lazy to write an additional check for boundary values.

7. Forgotten resource limits

This problem occurs when manually managing memory, as well as when working with databases, or when creating dimensionless arrays. Be careful with array delimiters, check databases when you merge, and be sure to specify boundary values when accessing RAM directly.

8. Accessing freed memory

This error is the most popular among C programmers, since here, after finishing work with a memory block, the cells are necessarily freed. But in other languages, similar problems occur, for example, in the case of forced cleaning in order to save resources.

The essence of the problem lies in the fact that the program accesses the freed memory after it has been cleared. And, of course, it does not receive the expected data. The bug is extremely popular even among experienced developers. Using the services of a trusted financial software development company, you can avoid such a failure.

9. SQL injection and OS commands

In the database development process, it is important to think through all the important aspects in advance. To do this, there are auxiliary tools that generate realistic test data for databases before entering your real personal information into the database, for example –  test data generator. The reasons for SQL injection(Programming errors) are the low level of site protection. Most often, they are carried out by sending messages from users (feedback form, adding an entry to the forum, contacting the chat, etc.). If the security hole is not closed, the attacker sends malicious code through these forms, and the server starts executing it. And the hacker gets access to all databases.

The situation is similar with OS commands. If you give permission to a program to operate ready-made system commands, it is imperative to put up protection against intruders so that the application executes only those commands that were specified by the developer, but could not use anything else.

10. Risky algorithms

This Programming errors consists of the fact that the programmer either begins to “reinvent the wheel” when trying to protect the personal data of users or other important information, or, conversely, uses the first option found, without even checking it for vulnerabilities.

With the first case, everything is clear. Data protection is not an area where you should rely only on your rather modest capabilities. An example of the second case is using the SHA-1 hashtag algorithm. If you use the search, you will very quickly find out that this algorithm is already outdated, many vulnerabilities have been found in it, for which more than one virus has been written. Therefore, it is better to use SHA-2 or SHA-3.