The devil is in the (implementation) details Sun, San-Tsai; Beznosov, Konstantin
Proceedings of the 2012 ACM conference on Computer and communications security,
10/2012
Conference Proceeding
Millions of web users today employ their Facebook accounts to sign into more than one million relying party (RP) websites. This web-based single sign-on (SSO) scheme is enabled by OAuth 2.0, a web ...resource authorization protocol that has been adopted by major service providers. The OAuth 2.0 protocol has proven secure by several formal methods, but whether it is indeed secure in practice remains an open question. We examine the implementations of three major OAuth identity providers (IdP) (Facebook, Microsoft, and Google) and 96 popular RP websites that support the use of Facebook accounts for login. Our results uncover several critical vulnerabilities that allow an attacker to gain unauthorized access to the victim user's profile and social graph, and impersonate the victim on the RP website. Closer examination reveals that these vulnerabilities are caused by a set of design decisions that trade security for implementation simplicity. To improve the security of OAuth 2.0 SSO systems in real-world settings, we suggest simple and practical improvements to the design and implementation of IdPs and RPs that can be adopted gradually by individual sites.
OpenID 2.0 is a user-centric Web single sign-on protocol with over one billion OpenID-enabled user accounts, and tens of thousands of supporting websites. While the security of the protocol is ...clearly critical, so far its security analysis has only been done in a partial and ad-hoc manner. This paper presents the results of a systematic analysis of the protocol using both formal model checking and an empirical evaluation of 132 popular websites that support OpenID. Our formal analysis reveals that the protocol does not guarantee the authenticity and integrity of the authentication request, and it lacks contextual bindings among the protocol messages and the browser. The results of our empirical evaluation suggest that many OpenID-enabled websites are vulnerable to a series of cross-site request forgery attacks (CSRF) that either allow an attacker to stealthily force a victim user to sign into the OpenID supporting website and launch subsequent CSRF attacks (81%), or force a victim to sign in as the attacker in order to spoof the victim's personal information (77%). With additional capabilities (e.g., controlling a wireless access point), the adversary can impersonate the victim on 80% of the evaluated websites, and manipulate the victim's profile attributes by forging the extension parameters on 45% of those sites. Based on the insights from this analysis, we propose and evaluate a simple and scalable mitigation technique for OpenID-enabled websites, and an alternative man-in-the-middle defense mechanism for deployments of OpenID without SSL.
Highlights ► Novel discoveries on the function of protostomian GnRH were made from Aplysia californica . ► GnRH in A. californica (ap-GnRH) is not a reproductive activator. ► GnRH in A. californica ...(ap-GnRH) modulates motor output and neuronal properties.
Smartphones store sensitive and confidential data, e.g., business related documents or emails. If a smartphone is stolen, such data are at risk of disclosure. To mitigate this risk, modern ...smartphones allow users to enable data encryption, which uses a locking password to protect the data encryption key. Unfortunately, users either do not lock their devices at all, due to usability issues, or use weak and easy to guess 4-digit PINs. This makes the current approach of protecting confidential data-at-rest ineffective against password guessing attackers. To address this problem we design, implement and evaluate the Sidekick system — a system that uses a wearable device to decouple data encryption and smartphone locking. Evaluation of the Sidekick system revealed that the proposal can run on an 8-bit System-on-Chip, uses only 4 Kb/20 Kb of RAM/ROM, allows data encryption key fetching in less than two seconds, while lasting for more than a year on a single coin-cell battery.
Highlights • The de novo synthesis of ap-GnRH is restricted to the central nervous system. • Pedal and cerebral ganglia are the primary sites of ap-GnRH production. • ap-GnRH is absent in two ...reproductive organs: the ovotestis and bag cell neurons.
OpenID and OAuth are open and simple Web SSO protocols that have been adopted by major service providers, and millions of supporting Web sites. However, the average user’s perception of Web SSO is ...still poorly understood. Through several user studies, this work investigates users’ perceptions and concerns when using Web SSO for authentication. We found that our participants had several misconceptions and concerns that impeded their adoption. This ranged from their inadequate mental models of Web SSO, to their concerns about personal data exposure, and a reduction in perceived Web SSO value due to the employment of password management practices. Informed by our findings, we offer a Web SSO technology acceptance model, and suggest design improvements.
In vertebrates, gonadotropin-releasing hormone (GnRH) is a crucial decapeptide that activates the hypothalamic-pituitary-gonadal axis to ensure successful reproduction. Recently, a GnRH-like molecule ...has been isolated from a gastropod mollusk, Aplysia californica. This GnRH (ap-GnRH) is deduced to be an undecapeptide, and its function remains to be explored. Our previous study demonstrated that ap-GnRH did not stimulate a range of reproductive parameters. Instead, it affected acute behavioral and locomotive changes unrelated to reproduction. In this study, we used electrophysiology and retrograde tracing to further explore the central role of ap-GnRH. Sharp-electrode intracellular recordings revealed that ap-GnRH had diverse effects on central neurons that ranged from excitatory, inhibitory, to the alteration of membrane potential. Unexpectedly, extracellular recordings revealed that ap-GnRH suppressed the onset of electrical afterdischarge in bag cell neurons, suggesting an inhibitory effect on female reproduction. Lastly, using immunocytochemistry coupled with nickel backfill, we demonstrated that some ap-GnRH neurons projected to efferent nerves known to innervate the foot and parapodia, suggesting ap-GnRH may directly modulate the motor output of these peripheral tissues. Overall, our results suggested that in A. californica, ap-GnRH more likely functioned as a central modulator of complex behavior and motor regulation rather than as a conventional reproductive stimulator.
OpenIDemail enabled browser Sun, San-Tsai; Hawkey, Kirstie; Beznosov, Konstantin
Proceedings of the 6th ACM workshop on Digital identity management,
10/2010
Conference Proceeding
Current Web single sign-on (SSO) solutions impose a cognitive burden on web users and do not provide content-hosting and service providers (CSPs) with sufficient incentives to become relying parties ...(RPs). We propose a browser-based Web SSO solution that requires minimal user interaction and provide RPs with clear value propositions to motivate their adoption. Our approach builds OpenID support into web browsers, hides OpenID identifiers from users by using their existing email accounts, extends the OpenID protocol to perform authentication directly by browsers, and introduces an OpenIDAuth HTTP access authentication scheme to convey authenticated identities automatically into websites that support OpenID for authentication. Our solution embeds an intuitive and consistent login experience for web users in the browser; to motivate adoption by RPs, it provides them with instant marketable leads and the potential for gradual engagement of site visitors.
Abstract Gonadotropin-releasing hormone (GnRH) is indispensable for reproductive activation in all vertebrates. Although several GnRH-like molecules have been isolated from non-chordates, the ...function of GnRH in these taxa remains unclear. We previously isolated the full-length cDNA sequence of a prohormone containing a GnRH-like molecule, termed ap-GnRH, from the gastropod mollusk, Aplysia californica . In this study, we characterized the distribution and quantity of ap-GnRH peptide in several central and peripheral tissues of A. californica . Further, we performed in vivo and in vitro studies to explore the function of ap-GnRH in these animals. Immunohistochemistry and radioimmunoassay using specific antisera against ap-GnRH showed that pedal ganglia contained the highest level of ap-GnRH peptide, followed by cerebral ganglia, abdominal ganglia, and then buccal ganglia. Ovotestis did not contain detectable levels of ap-GnRH peptide. Injection of sexually mature and immature animals with synthetic ap-GnRH over a course of 10–14 days had no effects on ovotestis mass, reproductive tract mass, egg-laying, and penile eversion. ap-GnRH also failed to alter oocyte growth and egg-laying hormone accumulation and secretion. Interestingly, ap-GnRH injection triggered acute behavioral responses including the stimulation of parapodial opening, inhibition of feeding, and promotion of substrate attachment. Our results showed that in A. californica , ap-GnRH could modulate a wide range of behavioral attributes. Most strikingly, ap-GnRH is not involved in the acute activation of reproduction in a fashion similar to vertebrate GnRH.
Web 2.0 users need usable mechanisms for sharing their content with each other in a controlled manner across boundaries of content-hosting or application-service providers (CSPs). In this paper, we ...describe the architecture, design, and implementation of a proposed system for Web 2.0 content sharing across CSPs. With our approach, users use their existing email account to login to CSPs, and content owners use their email-based contact-lists to specify access policies. Users are assumed to be equipped only with a Web browser and CSPs do not need to change their existing access-control mechanisms. In addition, policy statements are URI-addressable, and the same access policies can be reused and enforced across CSPs.
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