CSSXC: Context-sensitive Sanitization Framework for Web Applications against XSS Vulnerabilities in Cloud Environments

AbstractThis paper presents a context-sensitive sanitization based XSS defensive framework for the cloud environment. It discovers all the hidden injection points in HTML5-based web applications deployed on the platforms of cloud and sanitizes the XSS attack payloads injected in such points in a context sensitive manner. The identification of such injection points permits our technique to retrieve each possible web page of application, allowing a wider exploration and accelerating the process of applying the sanitizers on the untrusted variables of web application. The XSS attack mitigation capability of our framework was evaluated on web applications deployed for the cloud users in the cloud environment. The experimental results reveal that this technique detects the XSS attack payloads with minimum rate of false negatives and less runtime overhead

Understanding emerging client-Side web vulnerabilities using dynamic program analysis

Today's Web heavily relies on JavaScript as it is the main driving force behind the plethora of Web applications that we enjoy daily. The complexity and amount of this client-side code have been steadily increasing over the years. At the same time, new vulnerabilities keep being uncovered, for which we mostly rely on manual analysis of security experts. Unfortunately, such manual efforts do not scale to the problem space at hand. Therefore in this thesis, we present techniques capable of finding vulnerabilities automatically and at scale that originate from malicious inputs to postMessage handlers, polluted prototypes, and client-side storage mechanisms. Our results highlight that the investigated vulnerabilities are prevalent even among the most popular sites, showing the need for automated systems that help developers uncover them in a timely manner. Using the insights gained during our empirical studies, we provide recommendations for developers and browser vendors to tackle the underlying problems in the future. Furthermore, we show that security mechanisms designed to mitigate such and similar issues cannot currently be deployed by first-party applications due to their reliance on third-party functionality. This leaves developers in a no-win situation, in which either functionality can be preserved or security enforced.JavaScript ist die treibende Kraft hinter all den Web Applikationen, die wir heutzutage täglich nutzen. Allerdings ist über die Zeit hinweg gesehen die Masse, aber auch die Komplexität, von Client-seitigem JavaScript Code stetig gestiegen. Außerdem finden Sicherheitsexperten immer wieder neue Arten von Verwundbarkeiten, meistens durch manuelle Analyse des Codes. In diesem Werk untersuchen wir deshalb Methodiken, mit denen wir automatisch Verwundbarkeiten finden können, die von postMessages, veränderten Prototypen, oder Werten aus Client-seitigen Persistenzmechnanismen stammen. Unsere Ergebnisse zeigen, dass die untersuchten Schwachstellen selbst unter den populärsten Websites weit verbreitet sind, was den Bedarf an automatisierten Systemen zeigt, die Entwickler bei der rechtzeitigen Aufdeckung dieser Schwachstellen unterstützen. Anhand der in unseren empirischen Studien gewonnenen Erkenntnissen geben wir Empfehlungen für Entwickler und Browser-Anbieter, um die zugrunde liegenden Probleme in Zukunft anzugehen. Zudem zeigen wir auf, dass Sicherheitsmechanismen, die solche und ähnliche Probleme mitigieren sollen, derzeit nicht von Seitenbetreibern eingesetzt werden können, da sie auf die Funktionalität von Drittanbietern angewiesen sind. Dies zwingt den Seitenbetreiber dazu, zwischen Funktionalität und Sicherheit zu wählen

Modeling security and privacy requirements: A use case-driven approach

Context: Modern internet-based services, ranging from food-delivery to home-caring, leverage the availability of multiple programmable devices to provide handy services tailored to end-user needs. These services are delivered through an ecosystem of device-specific software components and interfaces (e.g., mobile and wearable device applications). Since they often handle private information (e.g., location and health status), their security and privacy requirements are of crucial importance. Defining and analyzing those requirements is a significant challenge due to the multiple types of software components and devices integrated into software ecosystems. Each software component presents peculiarities that often depend on the context and the devices the component interact with, and that must be considered when dealing with security and privacy requirements. Objective: In this paper, we propose, apply, and assess a modeling method that supports the specification of security and privacy requirements in a structured and analyzable form. Our motivation is that, in many contexts, use cases are common practice for the elicitation of functional requirements and should also be adapted for describing security requirements. Method: We integrate an existing approach for modeling security and privacy requirements in terms of security threats, their mitigations, and their relations to use cases in a misuse case diagram. We introduce new security-related templates, i.e., a mitigation template and a misuse case template for specifying mitigation schemes and misuse case specifications in a structured and analyzable manner. Natural language processing can then be used to automatically report inconsistencies among artifacts and between the templates and specifications. Results: We successfully applied our approach to an industrial healthcare project and report lessons learned and results from structured interviews with engineers. Conclusion: Since our approach supports the precise specification and analysis of security threats, threat scenarios and their mitigations, it also supports decision making and the analysis of compliance to standards

Modeling Security and Privacy Requirements for Mobile Applications: a Use Case-driven Approach

Defining and addressing security and privacy requirements in mobile apps is a significant challenge due to the high level of transparency regarding users' (private) information. In this paper, we propose, apply, and assess a modeling method that supports the specification of security and privacy requirements of mobile apps in a structured and analyzable form. Our motivation is that, in many contexts including mobile app development, use cases are common practice for the elicitation and analysis of functional requirements and should also be adapted for describing security requirements. We integrate and adapt an existing approach for modeling security and privacy requirements in terms of security threats, their mitigations, and their relations to use cases in a misuse case diagram. We introduce new security-related templates, i.e., a mitigation template and a misuse case template for specifying mitigation schemes and misuse case specifications in a structured and analyzable manner. Natural language processing can then be used to automatically detect and report inconsistencies among artifacts and between the templates and specifications. Since our approach supports stakeholders in precisely specifying and checking security threats, threat scenarios and their mitigations, it is expected to help with decision making and compliance with standards for improving security. We successfully applied our approach to industrial mobile apps and report lessons learned and results from structured interviews with engineers

Modeling Security and Privacy Requirements: a Use Case-Driven Approach

Context: Modern internet-based services, ranging from food-delivery to home-caring, leverage the availability of multiple programmable devices to provide handy services tailored to end-user needs. These services are delivered through an ecosystem of device-specific software components and interfaces (e.g., mobile and wearable device applications). Since they often handle private information (e.g., location and health status), their security and privacy requirements are of crucial importance. Defining and analyzing those requirements is a significant challenge due to the multiple types of software components and devices integrated into software ecosystems. Each software component presents peculiarities that often depend on the context and the devices the component interact with, and that must be considered when dealing with security and privacy requirements. Objective: In this paper, we propose, apply, and assess a modeling method that supports the specification of security and privacy requirements in a structured and analyzable form. Our motivation is that, in many contexts, use cases are common practice for the elicitation of functional requirements and should also be adapted for describing security requirements. Method: We integrate an existing approach for modeling security and privacy requirements in terms of security threats, their mitigations, and their relations to use cases in a misuse case diagram. We introduce new security-related templates, i.e., a mitigation template and a misuse case template for specifying mitigation schemes and misuse case specifications in a structured and analyzable manner. Natural language processing can then be used to automatically report inconsistencies among artifacts and between the templates and specifications. Results: We successfully applied our approach to an industrial healthcare project and report lessons learned and results from structured interviews with engineers. Conclusion: Since our approach supports the precise specification and analysis of security threats, threat scenarios and their mitigations, it also supports decision making and the analysis of compliance to standards

Automated intrusion recovery for web applications

Thesis (Ph. D.)--Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2013.Cataloged from PDF version of thesis.Includes bibliographical references (pages 93-97).In this dissertation, we develop recovery techniques for web applications and demonstrate that automated recovery from intrusions and user mistakes is practical as well as effective. Web applications play a critical role in users' lives today, making them an attractive target for attackers. New vulnerabilities are routinely found in web application software, and even if the software is bug-free, administrators may make security mistakes such as misconfiguring permissions; these bugs and mistakes virtually guarantee that every application will eventually be compromised. To clean up after a successful attack, administrators need to find its entry point, track down its effects, and undo the attack's corruptions while preserving legitimate changes. Today this is all done manually, which results in days of wasted effort with no guarantee that all traces of the attack have been found or that no legitimate changes were lost. To address this problem, we propose that automated intrusion recovery should be an integral part of web application platforms. This work develops several ideas-retroactive patching, automated UI replay, dependency tracking, patch-based auditing, and distributed repair-that together recover from past attacks that exploited a vulnerability, by retroactively fixing the vulnerability and repairing the system state to make it appear as if the vulnerability never existed. Repair tracks down and reverts effects of the attack on other users within the same application and on other applications, while preserving legitimate changes. Using techniques resulting from these ideas, an administrator can easily recover from past attacks that exploited a bug using nothing more than a patch fixing the bug, with no manual effort on her part to find the attack or track its effects. The same techniques can also recover from attacks that exploit past configuration mistakes-the administrator only has to point out the past request that resulted in the mistake. We built three prototype systems, WARP, POIROT, and AIRE, to explore these ideas. Using these systems, we demonstrate that we can recover from challenging attacks in real distributed web applications with little or no changes to application source code; that recovery time is a fraction of the original execution time for attacks with a few affected requests; and that support for recovery adds modest runtime overhead during the application's normal operation.by Ramesh Chandra.Ph.D

Detection of Lightweight Directory Access Protocol Query Injection Attacks in Web Applications

The Lightweight Directory Access Protocol (LDAP) is a common protocol used in organizations for Directory Service. LDAP is popular because of its features such as representation of data objects in hierarchical form, being open source and relying on TCP/IP, which is necessary for Internet access. However, with LDAP being used in a large number of web applications, different types of LDAP injection attacks are becoming common. The idea behind LDAP injection attacks is to take advantage of an application not validating inputs before being used as part of LDAP queries. An attacker can provide inputs that may result in alteration of intended LDAP query structure. LDAP injection attacks can lead to various types of security breaches including (i) Login Bypass, (ii) Information Disclosure, (iii) Privilege Escalation, and (iv) Information Alteration. Despite many research efforts focused on traditional SQL Injection attacks, most of the proposed techniques cannot be suitably applied for mitigating LDAP injection attacks due to syntactic and semantic differences between LDAP and SQL queries. Many implemented web applications remain vulnerable to LDAP injection attacks. In particular, there has been little attention for testing web applications to detect the presence of LDAP query injection attacks. The aim of this thesis is two folds: First, study various types of LDAP injection attacks and vulnerabilities reported in the literature. The planned research is to critically examine and evaluate existing injection mitigation techniques using a set of open source applications reported to be vulnerable to LDAP query injection attacks. Second, propose an approach to detect LDAP injection attacks by generating test cases when developing secure web applications. In particular, the thesis focuses on specifying signatures for detecting LDAP injection attack types using Object Constraint Language (OCL) and evaluates the proposed approach using PHP web applications. We also measure the effectiveness of generated test cases using a metric named Mutation Score

Security Aspects in Modern Web Applications

World Wide Webin taustalla olevat tekniikat kehitettiin alun perin helpottamaan tiedon jakamista. Tämä jaettu tieto oli aluksi muuttumatonta tai harvoin muuttuvaa, mutta webin yleistyminen muutti tilanteen. Yleistyminen teki web-selaimesta nopeasti yleismaailmallisen ohjelmiston sovellusten tuottamiselle ja käyttäjälle välittämiselle. Vaikka nämä web-sovelluksiksi kutsuttavat ohjelmistot olivat alkujaan työpöytäsovelluksia monin tavoin huonompia, muuttui tilanne nopeasti. Web-sovelluksissa käytettävät tekniikat, kuten JavaScript ja CSS, sekä webselainten moninaisuus muodostavat yhdessä erin aisten kysymysten sekamelskan, jota vastaavaa ei työpöytäsovelluksissa ole. Eräs tärkeä kysymys on, miten sovellusten käyttäjien lähettämä ja käyttämä tieto turvataan. Tässä diplomityössä tutkitaan ja kuvaterään web-sovelluksen tietoturvallisuutta ja tietoturvaratkaisuja. Arvioiminen vaatii tiet astä sekä yleisistä tietoturvallisuuskysymyksistä että erityisesti web-sovelluksiin liittyvistä kysymyksistä. Ensimmäisenä tutustutaan tietoturvallisuuden peruskysymyksiin ja käsitteisiin, joiden ymmärtäminen on välttämätöntä. Perusteiden jälkeen käsillään pääsynhallintaa ja sovellusohjelmistojen tietoturvallisuutta. Ensimmäinen osa päättyy web-sovellusten ja niihin liittyvien tietoturvallisuuskysymysten esittelyyn. Jälkimmäinen osa diplomity tä soveltaa käsiteltyjä teorioita ja menetelmiä erään web-sovelluksen tapaustutkimuksessa. Tapaustutkimuksessa kuvataan ja arvioidaan sovelluksen tietoturvallisuutta sekä lopuksi esitellään löydettyjä haavoittuvuuksia ja ratkaisuja näihin haavoittuvuuksiin. Vaikka joidenkin ohjelmistojen tietoturvallisuuden arviointimenetelmien soveltamisessa olikin ongelmia, saatiin tapaustutkimuksen tuloksena tärkeää tietoa heikkouksista ohjelmiston tietoturvallisuudessa ja hyviä esityksiä näiden heikkouksien poistamiseksi. Esitykset toteuttamalla parannettiin sekä nykyistä tietoturvallisuutta että vakuututtiin siitä, että heikkouksia esintyy jatkossa vähemmän.Technologies behind the World Wide Web were created initially to ease sharing of static data in form of web pages. Popularity of the Web grew rapidly and led to adoption of web browser as a universal client for application delivery. Though initially inferior to desktop applications, these applications have caught up with their desktop counterparts in features and usability. These applications, called web applications, use multiple web technologies such as JavaScript and CSS and this multiplicity of web technologies combined with multiplicity of web browsers creates a unique brew of issues not found on the desktop. One of these issues is how data send and used by the applications' users is protected. In this thesis, security in one mature web application is described and assessed. Such an assessment requires knowledge of information security aspects both in the broader sense concerning all information systems and in the sense of aspects specific to web applications. Therefore, first introduced are the fundamental concepts of information security, building blocks for all the other sections. The fundamentals are followed by discussion of access control and security aspects in applications. The background part is concluded by discussion of web applications in general and of security questions specific to them. The latter part explores and applies these theories and methods in a case study of a mature web application. The case study first describes, then evaluates the subject and its security and concludes with discussion of some of the found vulnerabilities and solutions to them. Although there were some problems in application of security assessment methods, assessment results provided valuable information on the application's weaknesses and improvement proposals. Implementation of the proposals both improved current security and also gave assurance of fewer weaknesses in the future