43,020 research outputs found
Defending Against Insider Use of Digital Steganography
The trusted insider is among the most harmful and difficult to detect threats to information security, according to the Federal Plan for Information Assurance and Cyber Security Research and Development released in April 2006. By default, employees become trusted insiders when granted the set of privileges needed to do their jobs, which typically includes access to the Internet. It is generally presumed the insiders are loyally working to achieve the organization’s goals and objectives and would not abuse the privileges given to them. However, some insiders will inevitably abuse some of their privileges. For example, a trusted insider might abuse their privilege of access to the Internet to download, install, and use an information hiding tool, such as one of the hundreds of digital steganography applications available on the Internet, to steal sensitive, classified, or proprietary information. Effective countermeasures to this threat must begin with an organizational policy prohibiting installation of information hiding tools on user workstations and must also include automated tools capable of detecting attempts to download and use digital steganography applications. This paper will describe the threat from insider use of digital steganography applications; a new approach to detecting the presence or use of these applications; and extraction of hidden information when a known signature of one of these applications is detected. The analytical approach to steganalysis involves the development and use of computer forensic tools that can detect fingerprints and signatures of digital steganography applications. These tools can be employed in both an off-line forensic-based mode as well as a real-time network surveillance mode. Detection of fingerprints or signatures in either mode may lead to the discovery and extraction of hidden information. Accordingly, this approach represents a significant improvement over traditional blind detection techniques which typically only provide a probability that information may be hidden in a given file without providing a capability to extract any hidden information.
Keywords: insider, steganography, steganalysis, computer forensics, artifacts, fingerprints, hash values, signature
CamFlow: Managed Data-sharing for Cloud Services
A model of cloud services is emerging whereby a few trusted providers manage
the underlying hardware and communications whereas many companies build on this
infrastructure to offer higher level, cloud-hosted PaaS services and/or SaaS
applications. From the start, strong isolation between cloud tenants was seen
to be of paramount importance, provided first by virtual machines (VM) and
later by containers, which share the operating system (OS) kernel. Increasingly
it is the case that applications also require facilities to effect isolation
and protection of data managed by those applications. They also require
flexible data sharing with other applications, often across the traditional
cloud-isolation boundaries; for example, when government provides many related
services for its citizens on a common platform. Similar considerations apply to
the end-users of applications. But in particular, the incorporation of cloud
services within `Internet of Things' architectures is driving the requirements
for both protection and cross-application data sharing.
These concerns relate to the management of data. Traditional access control
is application and principal/role specific, applied at policy enforcement
points, after which there is no subsequent control over where data flows; a
crucial issue once data has left its owner's control by cloud-hosted
applications and within cloud-services. Information Flow Control (IFC), in
addition, offers system-wide, end-to-end, flow control based on the properties
of the data. We discuss the potential of cloud-deployed IFC for enforcing
owners' dataflow policy with regard to protection and sharing, as well as
safeguarding against malicious or buggy software. In addition, the audit log
associated with IFC provides transparency, giving configurable system-wide
visibility over data flows. [...]Comment: 14 pages, 8 figure
SafeWeb: A Middleware for Securing Ruby-Based Web Applications
Web applications in many domains such as healthcare and finance must process sensitive data, while complying with legal policies regarding the release of different classes of data to different parties. Currently, software bugs may lead to irreversible disclosure of confidential data in multi-tier web applications. An open challenge is how developers can guarantee these web applications only ever release sensitive data to authorised users without costly, recurring security audits.
Our solution is to provide a trusted middleware that acts as a “safety net” to event-based enterprise web applications by preventing harmful data disclosure before it happens. We describe the design and implementation of SafeWeb, a Ruby-based middleware that associates data with security labels and transparently tracks their propagation at different granularities across a multi-tier web architecture with storage and complex event processing. For efficiency, maintainability and ease-of-use, SafeWeb exploits the dynamic features of the Ruby programming language to achieve label propagation and data flow enforcement. We evaluate SafeWeb by reporting our experience of implementing a web-based cancer treatment application and deploying it as part of the UK National Health Service (NHS)
Quire: Lightweight Provenance for Smart Phone Operating Systems
Smartphone apps often run with full privileges to access the network and
sensitive local resources, making it difficult for remote systems to have any
trust in the provenance of network connections they receive. Even within the
phone, different apps with different privileges can communicate with one
another, allowing one app to trick another into improperly exercising its
privileges (a Confused Deputy attack). In Quire, we engineered two new security
mechanisms into Android to address these issues. First, we track the call chain
of IPCs, allowing an app the choice of operating with the diminished privileges
of its callers or to act explicitly on its own behalf. Second, a lightweight
signature scheme allows any app to create a signed statement that can be
verified anywhere inside the phone. Both of these mechanisms are reflected in
network RPCs, allowing remote systems visibility into the state of the phone
when an RPC is made. We demonstrate the usefulness of Quire with two example
applications. We built an advertising service, running distinctly from the app
which wants to display ads, which can validate clicks passed to it from its
host. We also built a payment service, allowing an app to issue a request which
the payment service validates with the user. An app cannot not forge a payment
request by directly connecting to the remote server, nor can the local payment
service tamper with the request
A Shibboleth-protected privilege management infrastructure for e-science education
Simplifying access to and usage of large scale compute resources via the grid is of critical importance to encourage the uptake of e-research. Security is one aspect that needs to be made as simple as possible for end users. The ESP-Grid and DyVOSE projects at the National e-Science Centre (NeSC) at the University of Glasgow are investigating security technologies which will make the end-user experience of using the grid easier and more secure. In this paper, we outline how simplified (from the user experience) authentication and authorization of users are achieved through single usernames and passwords at users' home institutions. This infrastructure, which will be applied in the second year of the grid computing module part of the advanced MSc in Computing Science at the University of Glasgow, combines grid portal technology, the Internet2 Shibboleth Federated Access Control infrastructure, and the PERMS role-based access control technology. Through this infrastructure inter-institutional teaching can be supported where secure access to federated resources is made possible between sites. A key aspect of the work we describe here is the ability to support dynamic delegation of authority whereby local/remote administrators are able to dynamically assign meaningful privileges to remote/local users respectively in a trusted manner thus allowing for the dynamic establishment of virtual organizations with fine grained security at their heart
Providing secure remote access to legacy applications
While the widespread adoption of Internet and Intranet technology has been one of the exciting developments of recent years, many hospitals are finding that their data and legacy applications do not naturally fit into the new methods of dissemination. Existing applications often rely on isolation or trusted networks for their access control or security, whereas untrusted wide area networks pay little attention to the authenticity, integrity or confidentiality of the data they transport. Many hospitals do not have the resources to develop new ''network-ready'' versions of existing centralised applications. In this paper, we examine the issues that must be considered when providing network access to an existing health care application, and we describe how we have implemented the proposed solution in one healthcare application namely the diabetic register at Hope Hospital. We describe the architecture that allows remote access to the legacy application, providing it with encrypted communications and strongly authenticated access control but without requiring any modifications to the underlying application. As well as comparing alternative ways of implementing such a system, we also consider issues relating to usability and manageability, such as password management
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