A Covert Data Transport Protocol

Both enterprise and national firewalls filter network connections. For data forensics and botnet removal applications, it is important to establish the information source. In this paper, we describe a data transport layer which allows a client to transfer encrypted data that provides no discernible information regarding the data source. We use a domain generation algorithm (DGA) to encode AES encrypted data into domain names that current tools are unable to reliably differentiate from valid domain names. The domain names are registered using (free) dynamic DNS services. The data transmission format is not vulnerable to Deep Packet Inspection (DPI).Comment: 8 pages, 10 figures, conferenc

PROVIDE: hiding from automated network scans with proofs of identity

Network scanners are a valuable tool for researchers and administrators, however they are also used by malicious actors to identify vulnerable hosts on a network. Upon the disclosure of a security vulnerability, scans are launched within hours. These opportunistic attackers enumerate blocks of IP addresses in hope of discovering an exploitable host. Fortunately, defensive measures such as port knocking protocols (PKPs) allow a service to remain stealth to unauthorized IP addresses. The service is revealed only when a client includes a special authentication token (AT) in the IP/TCP header. However this AT is generated from a secret shared between the clients/servers and distributed manually to each endpoint. As a result, these defense measures have failed to be widely adopted by other protocols such as HTTP/S due to challenges in distributing the shared secrets. In this paper we propose a scalable solution to this problem for services accessed by domain name. We make the following observation: automated network scanners access servers by IP address, while legitimate clients access the server by name. Therefore a service should only reveal itself to clients who know its name. Based on this principal, we have created a proof of the verifier’s identity (a.k.a. PROVIDE) protocol that allows a prover (legitimate user) to convince a verifier (service) that it is knowledgeable of the verifier’s identity. We present a PROVIDE implementation using a PKP and DNS (PKP+DNS) that uses DNS TXT records to distribute identification tokens (IDT) while DNS PTR records for the service’s domain name are prohibited to prevent reverse DNS lookups. Clients are modified to make an additional DNS TXT query to obtain the IDT which is used by the PKP to generate an AT. The inclusion of an AT in the packet header, generated from the DNS TXT query, is proof the client knows the service’s identity. We analyze the effectiveness of this mechanism with respect to brute force attempts for various strength ATs and discuss practical considerations.This work has been supported by the National Science Foundation (NSF) awards #1430145, #1414119, and #1012798

NSEC5, DNSSEC authenticated denial of existence

The Domain Name System Security Extensions (DNSSEC) introduced two resource records (RR) for authenticated denial of existence: the NSEC RR and the NSEC3 RR. This document introduces NSEC5 as an alternative mechanism for DNSSEC authenticated denial of existence. NSEC5 uses verifiable random functions (VRFs) to prevent offline enumeration of zone contents. NSEC5 also protects the integrity of the zone contents even if an adversary compromises one of the authoritative servers for the zone. Integrity is preserved because NSEC5 does not require private zone-signing keys to be present on all authoritative servers for the zone, in contrast to DNSSEC online signing schemes like NSEC3 White Lies.https://datatracker.ietf.org/doc/draft-vcelak-nsec5/First author draf

HLOC: Hints-Based Geolocation Leveraging Multiple Measurement Frameworks

Geographically locating an IP address is of interest for many purposes. There are two major ways to obtain the location of an IP address: querying commercial databases or conducting latency measurements. For structural Internet nodes, such as routers, commercial databases are limited by low accuracy, while current measurement-based approaches overwhelm users with setup overhead and scalability issues. In this work we present our system HLOC, aiming to combine the ease of database use with the accuracy of latency measurements. We evaluate HLOC on a comprehensive router data set of 1.4M IPv4 and 183k IPv6 routers. HLOC first extracts location hints from rDNS names, and then conducts multi-tier latency measurements. Configuration complexity is minimized by using publicly available large-scale measurement frameworks such as RIPE Atlas. Using this measurement, we can confirm or disprove the location hints found in domain names. We publicly release HLOC's ready-to-use source code, enabling researchers to easily increase geolocation accuracy with minimum overhead.Comment: As published in TMA'17 conference: http://tma.ifip.org/main-conference

Evaluation of Anonymized ONS Queries

Electronic Product Code (EPC) is the basis of a pervasive infrastructure for the automatic identification of objects on supply chain applications (e.g., pharmaceutical or military applications). This infrastructure relies on the use of the (1) Radio Frequency Identification (RFID) technology to tag objects in motion and (2) distributed services providing information about objects via the Internet. A lookup service, called the Object Name Service (ONS) and based on the use of the Domain Name System (DNS), can be publicly accessed by EPC applications looking for information associated with tagged objects. Privacy issues may affect corporate infrastructures based on EPC technologies if their lookup service is not properly protected. A possible solution to mitigate these issues is the use of online anonymity. We present an evaluation experiment that compares the of use of Tor (The second generation Onion Router) on a global ONS/DNS setup, with respect to benefits, limitations, and latency.Comment: 14 page

XML Schema-based Minification for Communication of Security Information and Event Management (SIEM) Systems in Cloud Environments

XML-based communication governs most of today's systems communication, due to its capability of representing complex structural and hierarchical data. However, XML document structure is considered a huge and bulky data that can be reduced to minimize bandwidth usage, transmission time, and maximize performance. This contributes to a more efficient and utilized resource usage. In cloud environments, this affects the amount of money the consumer pays. Several techniques are used to achieve this goal. This paper discusses these techniques and proposes a new XML Schema-based Minification technique. The proposed technique works on XML Structure reduction using minification. The proposed technique provides a separation between the meaningful names and the underlying minified names, which enhances software/code readability. This technique is applied to Intrusion Detection Message Exchange Format (IDMEF) messages, as part of Security Information and Event Management (SIEM) system communication hosted on Microsoft Azure Cloud. Test results show message size reduction ranging from 8.15% to 50.34% in the raw message, without using time-consuming compression techniques. Adding GZip compression to the proposed technique produces 66.1% shorter message size compared to original XML messages.Comment: XML, JSON, Minification, XML Schema, Cloud, Log, Communication, Compression, XMill, GZip, Code Generation, Code Readability, 9 pages, 12 figures, 5 tables, Journal Articl