Search results
Results From The WOW.Com Content Network
A classification of SQL injection attacking vector as of 2010. In computing, SQL injection is a code injection technique used to attack data-driven applications, in which malicious SQL statements are inserted into an entry field for execution (e.g. to dump the database contents to the attacker).
An SQL injection takes advantage of SQL syntax to inject malicious commands that can read or modify a database or compromise the meaning of the original query. [13] For example, consider a web page that has two text fields which allow users to enter a username and a password.
Most of these are only useful for detecting bad format strings that are known at compile-time. If the format string may come from the user or from a source external to the application, the application must validate the format string before using it. Care must also be taken if the application generates or selects format strings on the fly.
To learn a password from a hash is to find a string which, when input into the hash function, creates that same hash. This is the same as inverting the hash function. Though brute-force attacks (e.g. dictionary attacks) may be used to try to invert a hash function, they can become infeasible when the set of possible passwords is large enough.
Major DBMSs, including SQLite, [5] MySQL, [6] Oracle, [7] IBM Db2, [8] Microsoft SQL Server [9] and PostgreSQL [10] support prepared statements. Prepared statements are normally executed through a non-SQL binary protocol for efficiency and protection from SQL injection, but with some DBMSs such as MySQL prepared statements are also available using a SQL syntax for debugging purposes.
Malicious users are likely to invent new kinds of representations of incorrect data. For example, if a program attempts to reject accessing the file "/etc/passwd", a cracker might pass another variant of this file name, like "/etc/./passwd". Canonicalization libraries can be employed to avoid bugs due to non-canonical input.
As with non-Java applications, security vulnerabilities can stem from parts of the platform which may not initially appear to be security-related. For example, in 2011, Oracle issued a security fix for a bug in the Double.parseDouble method. [2] This method converts a string such as "12.34" into the equivalent double-precision floating point ...
It is common for a web application to store in a database the hash value of a user's password. Without a salt, a successful SQL injection attack may yield easily crackable passwords. Because many users re-use passwords for multiple sites, the use of a salt is an important component of overall web application security. [14]