Victor Le Pochat (imec-DistriNet, KU Leuven), Tom Van Goethem (imec-DistriNet, KU Leuven), Samaneh Tajalizadehkhoob (Delft University of Technology), Maciej Korczyński (Grenoble Alps University), Wouter Joosen (imec-DistriNet, KU Leuven)

In order to evaluate the prevalence of security and privacy practices on a representative sample of the Web, researchers rely on website popularity rankings such as the Alexa list. While the validity and representativeness of these rankings are rarely questioned, our findings show the contrary: we show for four main rankings how their inherent properties (similarity, stability, representativeness, responsiveness and benignness) affect their composition and therefore potentially skew the conclusions made in studies. Moreover, we find that it is trivial for an adversary to manipulate the composition of these lists. We are the first to empirically validate that the ranks of domains in each of the lists are easily altered, in the case of Alexa through as little as a single HTTP request. This allows adversaries to manipulate rankings on a large scale and insert malicious domains into whitelists or bend the outcome of research studies to their will. To overcome the limitations of such rankings, we propose improvements to reduce the fluctuations in list composition and guarantee better defenses against manipulation. To allow the research community to work with reliable and reproducible rankings, we provide Tranco, an improved ranking that we offer through an online service available at

View More Papers

Coconut: Threshold Issuance Selective Disclosure Credentials with Applications to...

Alberto Sonnino (University College London (UCL)), Mustafa Al-Bassam (University College London (UCL)), Shehar Bano (University College London (UCL)), Sarah Meiklejohn (University College London (UCL)), George Danezis (University College London (UCL))

Read More

Component-Based Formal Analysis of 5G-AKA: Channel Assumptions and Session...

Cas Cremers (CISPA Helmholtz Center for Information Security), Martin Dehnel-Wild (University of Oxford)

Read More

Neural Machine Translation Inspired Binary Code Similarity Comparison beyond...

Fei Zuo (University of South Carolina), Xiaopeng Li (University of South Carolina), Patrick Young (Temple University), Lannan Luo (University of South Carolina), Qiang Zeng (University of South Carolina), Zhexin Zhang (University of South Carolina)

Read More

IoTGuard: Dynamic Enforcement of Security and Safety Policy in...

Z. Berkay Celik (Penn State University), Gang Tan (Penn State University), Patrick McDaniel (Penn State University)

Read More