Improving SNI-based HTTPS Security Monitoring

International audienceRecent surveys show that the proportion of encrypted web traffic is quickly increasing. On one side, it provides users with essential properties of security and privacy, but on the other side, it raises important challenges and issues for organizations, related to the security monitoring of encrypted traffic (filtering, anomaly detection, etc.). This paper proposes to improve a recent technique for HTTPS traffic monitoring that is based on the Server Name Indication (SNI) field of TLS and which has been implemented in many firewall solutions. This method currently has some weaknesses that can be used to bypass firewalls by overwriting the SNI value of new TLS connections. Our investigation shows that 92% of the HTTPS websites surveyed in this paper can be accessed with a fake SNI. Our approach verifies the coherence between the real destination server and the claimed value of SNI by relying on a trusted DNS service. Experimental results show the ability to overcome the shortage of SNI-based monitoring by detecting forged SNI values while having a very small false positive rate (1.7%). The overhead of our solution only adds negligible delays to access HTTPS websites. The proposed method opens the door to improve global HTTPS monitoring and firewall systems

REISCH: incorporating lightweight and reliable algorithms into healthcare applications of WSNs

Healthcare institutions require advanced technology to collect patients' data accurately and continuously. The tradition technologies still suffer from two problems: performance and security efficiency. The existing research has serious drawbacks when using public-key mechanisms such as digital signature algorithms. In this paper, we propose Reliable and Efficient Integrity Scheme for Data Collection in HWSN (REISCH) to alleviate these problems by using secure and lightweight signature algorithms. The results of the performance analysis indicate that our scheme provides high efficiency in data integration between sensors and server (saves more than 24% of alive sensors compared to traditional algorithms). Additionally, we use Automated Validation of Internet Security Protocols and Applications (AVISPA) to validate the security procedures in our scheme. Security analysis results confirm that REISCH is safe against some well-known attacks

HTTPS通信におけるクライアント・サーバ関係のIRM分析

Sedan början på 80-talet går det att konstatera en tydlig förändring i den svenska kriminalpolitiken som kännetecknas av mer strafftänkande och mindre fokus på behandling och återanpassning av kriminella. Denna förändrade kriminalpolitik kännetecknas bl.a. av höjda straffskalor, allt fler utdömda livstidsdomar och en ökande fängelsebeläggning. Men det blir också allt mer tydligt i den politiska retoriken att kriminalpolitiken har förändrats; det talas allt mer om säkerhet, kontroll och att använda hårdare tag mot brottslingarna. I uppsatsen studeras, med diskursanalys som metod, denna förändrade kriminalpolitik utifrån retoriken i den politiska debatten. Det material som studeras är fyra debattartiklar som publicerades på Dagens Nyheters debattsida i samband med flera i media uppmärksammade rymningar från kriminalvården 2004

Enhancing System Transparency, Trust, and Privacy with Internet Measurement

While on the Internet, users participate in many systems designed to protect their information’s security. Protection of the user’s information can depend on several technical properties, including transparency, trust, and privacy. Preserving these properties is challenging due to the scale and distributed nature of the Internet; no single actor has control over these features. Instead, the systems are designed to provide them, even in the face of attackers. However, it is possible to utilize Internet measurement to better defend transparency, trust, and privacy. Internet measurement allows observation of many behaviors of distributed, Internet-connected systems. These new observations can be used to better defend the system they measure. In this dissertation, I explore four contexts in which Internet measurement can be used to the aid of end-users in Internet-centric, adversarial settings. First, I improve transparency into Internet censorship practices by developing new Internet measurement techniques. Then, I use Internet measurement to enable the deployment of end-to-middle censorship circumvention techniques to a half-million users. Next, I evaluate transparency and improve trust in the Web public-key infrastructure by combining Internet measurement techniques and using them to augment core components of the Web public-key infrastructure. Finally, I evaluate browser extensions that provide privacy to users on the web, providing insight for designers and simple recommendations for end-users. By focusing on end-user concerns in widely deployed systems critical to end-user security and privacy, Internet measurement enables improvements to transparency, trust, and privacy.PHDComputer Science & EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/163199/1/benvds_1.pd

Torrent Poisoning Protection with a Reverse Proxy Server

A Distributed Denial-of-Service attack uses multiple sources operating in concert to attack a network or site. A typical DDoS flood attack on a website targets a web server with multiple valid requests, exhausting the server’s resources. The participants in this attack are usually compromised/infected computers controlled by the attackers. There are several variations of this kind of attack, and torrent index poisoning is one. A Distributed Denial-of-Service (DDoS) attack using torrent poisoning, more specifically using index poisoning, is one of the most effective and disruptive types of attacks. These web flooding attacks originate from BitTorrent-based file-sharing communities, where the participants using the BitTorrent applications cannot detect their involvement. The antivirus and other tools cannot detect the altered torrent file, making the BitTorrent client target the webserver. The use of reverse proxy servers can block this type of request from reaching the web server, preventing the severity and impact on the service of the DDoS. In this paper, we analyze a torrent index poisoning DDoS to a higher education institution, the impact on the network systems and servers, and the mitigation measures implemented.info:eu-repo/semantics/publishedVersio