The essence of command injection attacks in web applications

Web applications typically interact with a back-end database to retrieve persistent data and then present the data to the user as dynamically generated output, such as HTML web pages. However, this interaction is commonly done through a low-level API by dynamically constructing query strings within a general-purpose programming language, such as Java. This low-level interaction is ad hoc because it does not take into account the structure of the output language. Accordingly, user inputs are treated as isolated lexical entities which, if not properly sanitized, can cause the web application to generate unintended output. This is called a command injection attack, which poses a serious threat to web application security. This paper presents the first formal definition of command injection attacks in the context of web applications, and gives a sound and complete algorithm for preventing them based on context-free grammars and compiler parsing techniques. Our key observation is that, for an attack to succeed, the input that gets propagated into the database query or the output document must change the intended syntactic structure of the query or document. Our definition and algorithm are general and apply to many forms of command injection attacks. We validate our approach with SqlCheckS, an implementation for the setting of SQL command injection attacks. We evaluated SqlCheckS on real-world web applications with systematically compiled real-world attack data as input. SqlCheckS produced no false positives or false negatives, incurred low runtime overhead, and applied straightforwardly to web applications written in different languages.

Web Application now days are an important part of our daily life. Attackers try to attack these web applications to gain valuable information about the users using these web applications. Attackers exploit vulnerabilities in a web application to gain user data. This paper describes in detail the most harmful attacks that occurs on vulnerable web applications that are: SQL Injection Attack, Cross-Site Scripting Attack (XSS) and Command Injection Attack and helps you understand mechanism for 3 different types of attacks how they take place, what threats they possess and what could be done to avoid them.

Most of the web applications are establishing the web session with the client. It is very important to protect the wireless networks against session hijacking attack. Session Hijack attack is easy to execute and difficult to detect. Wireless networks do not have specific boundary regions for the packets to be transferred. As the data packets are transferred in air, the chances of sniffing the network packets by the hackers or attackers are high by using the network sniffing tools. In this paper, we have proposed the Strong and Encrypted Session ID to prevent the session hijack attacks in web applications. Session ID is generated and the generated Session ID is encrypted, using a Secret Key Sharing algorithm and decrypted at the client side. We have tested the integrity of the session ID of length 32, 92 and 212 characters in a web application. Attacks are executed to capture the session ID of a web application. Our experimental results proved that 212 characters encrypted session ID completely prevents the session hijack attacks in web applications of wireless networks.

Timing attacks in web applications have been known for over a decade. Recently, new attacks have been reported to exploit timing techniques to probe sensitive information from web applications. In this paper, we present a tool to detect timing-based probing attacks in web applications. The main idea of our approach is to monitor the browser behaviors and identify anomalous timing behaviors. We prototyped our approach in the Google Chrome browser, and demonstrated its effectiveness.

Web applications security is indeed the most talked about and a vital topic of discussion in cyber security world. In the recent years, websites have become a main target for hackers. Attackers exploit vulnerabilities present in the web applications. Application level attacks are increasing day by day in websites. Some of the main application level attacks are SQL injections, cross-site scripting attacks, cookie poisoning attack, command injection attack, etc. According to OWASP, injection attacks occupy first place in breaching website security. There are several government, private and e-commerce websites that become victim of SQL injection attack each year. This paper includes the detailed study of mitigation strategies proposed by various researchers related to SQL injection attack. Furthermore, defence mechanism to safeguard web applications from SQLi attacks and future research directions is also indicated.KeywordsStructured query language injection (SQLi)OWASPVulnerabilitiesWebsitesMalicious queryAttacksDetection

XCS (Cross Channel Scripting) is a dangerous web application vulnerability, in which injection of the malicious code and attack execution is performed through network protocols. This vulnerability is the variant and sophistication concept of XSS (Cross-Site Scripting). We disclose a range of XCS attacks on embedded servers, which make use of electronic devices such as photo frames, cameras, wireless routers and wireless access points. All these devices have web interfaces, which permits an admin to perform various tasks on the device that is connecting from a web browser to the web server. An attack execution is carried by inserting malevolent code in the device, which is executed in the context of a legitimate user when he/she opens the page containing injected malicious code. This malevolent code can be inserted in the device through non web channels like SNMP (Simple Network Management Protocol), FTP (File Transfer Protocol) or NFS (Network File System). Unfortunately, the injected malicious code can fully compromise the security of devices, which are embedded in web servers. In this paper, a comprehensive analysis of the XCS exploitation and mitigation techniques have been presented.

Today almost all organizations have changed their traditional systems and have improved their performance using web-based applications. This process will make more profit and at the same time will increase the efficiency of their activities through customer support services and data transactions. Usually, web application take inputs from users through web form and send this input to get the response from database. Modern web-based application use web database to store all critical information such as user credentials, financial and payment information, company statistics etc. However error in validation of user input can cause database vulnerable to Structured Query Language Injection (SQLI) attack. By using SQLI attack, the attackers might insert malicious code in the user input and trying to gain access to the confidential and sensitive data from database. Security tester need to identify the appropriate test cases before starting exploiting SQL vulnerability in web-based application during testing phase. Identifying the test cases of a web application and analyzing the test results of an attack are important parts and consider as critical issues that affects the effectiveness of security testing. Thus, this research focused on the developing a framework for testing and detecting SQL injection vulnerability in web application. In this research, test cases will be generated automatically based on SQLI attack pattern and then the results will be executed automatically based on generated test cases. The primary focus in this paper is to develop a framework to automate security testing based on input injection attack pattern. To test our framework, we install a vulnerable web application and test result shows that the proposed framework can detect SQLI vulnerability successfully.

SQL injection is one of the major threats to the security of the web applications. Attackers try to gain unauthorized access to the database, which has vital and private information of the users. Many researchers have provided various techniques and practices to protect the web applications from attackers. There is a plethora of techniques available to perform SQL injection and usually not everyone is familiar with every attack. Hence, this kind of attack is still the most prevalent. In this paper, we have presented the types of SQL injections attacks and most dominant ways to prevent them.

Web application security has become real concern due to increase in attacks and data breaches. As Application becomes critical, complex and connected, the difficulty of achieving application security increases exponentially. Also there are tools and techniques to detect such attacks, threat and vulnerabilities that exist in application which developer prevent and mitigate the risk associated to it. This paper evaluates various web application attack detection mechanisms and how resistant they are against various attacking techniques. Such an evaluation is important for not only measuring the available attack defense against web application attacks but also identifying gaps to build effective solutions for different defense techniques on web application and use it for study. Based on the research, the limitations of these application attack detection techniques are identified and remedies proposed for improving the current state attack detection on web applications.

Predictive Analytics of Injection Attacks in Web Applications

Web applications are popular targets of security attacks. One common type of such attacks is SQL injection, where an attacker exploits faulty application code to execute maliciously crafted database queries. Bothstatic and dynamic approaches have been proposed to detect or prevent SQL injections; while dynamic approaches provide protection for deployed software, static approaches can detect potential vulnerabilities before software deployment. Previous static approaches are mostly based on tainted information flow tracking and have at least some of the following limitations: (1) they do not model the precise semantics of input sanitization routines; (2) they require manually written specifications, either for each query or for bug patterns; or (3) they are not fully automated and may require user intervention at various points in the analysis. In this paper, we address these limitations by proposing a precise, sound , and fully automated analysis technique for SQL injection. Our technique avoids the need for specifications by consideringas attacks those queries for which user input changes the intended syntactic structure of the generated query. It checks conformance to this policy byconservatively characterizing the values a string variable may assume with a context free grammar, tracking the nonterminals that represent user-modifiable data, and modeling string operations precisely as language transducers. We have implemented the proposed technique for PHP, the most widely-used web scripting language. Our tool successfully discovered previously unknown and sometimes subtle vulnerabilities in real-world programs, has a low false positive rate, and scales to large programs (with approx. 100K loc).

Web applications are becoming an important part of our daily life. So attacks against them also increases rapidly. Of these attacks, a major role is held by SQL injection attacks (SQLIA). This paper proposes a new method for preventing SQL injection attacks in JSP web applications. The basic idea is to check before execution, the intended structure of the SQL query. For this we use semantic comparison. Our focus is on stored procedure attack in which query will be formed within the database itself and so difficult to extract that query structure for validation. Also this attack is less considered in the literature.

Token based Detection and Neural Network based Reconstruction framework against code injection vulnerabilities

Warp is a system that helps users and administrators of web applications recover from intrusions such as SQL injection, cross-site scripting, and clickjacking attacks, while preserving legitimate user changes. Warp repairs from an intrusion by rolling back parts of the database to a version before the attack, and replaying subsequent legitimate actions. Warp allows administrators to retroactively patch security vulnerabilities---i.e., apply new security patches to past executions---to recover from intrusions without requiring the administrator to track down or even detect attacks. Warp's time-travel database allows fine-grained rollback of database rows, and enables repair to proceed concurrently with normal operation of a web application. Finally, Warp captures and replays user input at the level of a browser's DOM, to recover from attacks that involve a user's browser. For a web server running MediaWiki, Warp requires no application source code changes to recover from a range of common web application vulnerabilities with minimal user input at a cost of 24--27% in throughput and 2--3.2 GB/day in storage.

This chapter presents an approach to mitigate cross-site scripting (XSS) vulnerabilities in web-based environments using static and dynamic analysis. In order to identify and mitigate XSS attack vectors in web-based environments, a novel approach which successfully identifies and prevents XSS attack strings from injection points has been presented. Static analysis is the process of identifying whether a given web page is vulnerable to cross-site scripting. In addition, dynamic analysis approach is able to verify whether a given web application with vulnerable page assessed by static analysis approach is actually vulnerable. To identify XSS vulnerability of a web page, we make use of the Control-Flow Graph suggested by Lucca et al. The proposed approach involves a secure XSS interception layer placed in the client’s browser. To defend against XSS attacks, the proposed approach makes use of training phase, where every benevolent script is promoted by an identifier.