@inproceedings{sgnab-rctii-18, author = {Quirin Scheitle and Oliver Gasser and Theodor Nolte and Johanna Amann and Lexi Brent and Georg Carle and Ralph Holz and Thomas C. Schmidt and Matthias W{\"a}hlisch}, title = {{The Rise of Certificate Transparency and Its Implications on the Internet Ecosystem}}, booktitle = {Proc. of ACM Internet Measurement Conference (IMC)}, pages = {343--349}, year = {2018}, publisher = {ACM}, address = {New York}, abstract = {In this paper, we analyze the evolution of Certificate Transparency (CT) over time and explore the implications of exposing certificate DNS names from the perspective of security and privacy. We find that certificates in CT logs have seen exponential growth. Website support for CT has also constantly increased, with now a majority of established connections supporting CT. With the increasing deployment of CT, there are also concerns of information leakage due to all certificates being visible in CT logs. To understand this threat, we introduce a CT honeypot and show that data from CT logs is being used to identify targets for scanning campaigns only minutes after certificate issuance. We present and evaluate a methodology to learn and validate new subdomains from the vast number of domains extracted from CT logged certificates.}, file = {../papers/sgnab-rctii-18.pdf}, theme = {nsec|imeasurement}, code = {https://mediatum.ub.tum.de/1452291}, }