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Andrs E. Azprua #imv2020 Internet Censorship, DNS poisoning and Phishing in Venezuela Measuring from censorship to state-sponsored attacks Andrs E. Azprua #imv2020 @VEsinFiltro VEsinFiltro.com VENEZUELAN CONTEXT Critical failure


  1. Andrés E. Azpúrua #imv2020

  2. Internet Censorship, DNS poisoning and Phishing in Venezuela Measuring from censorship to state-sponsored attacks Andrés E. Azpúrua #imv2020

  3. @VEsinFiltro VEsinFiltro.com

  4. VENEZUELAN CONTEXT

  5. Critical failure of public services https://rpp.pe/ mundo/actualidad/venezuela-venezolanos-recogen-agua-del-contaminado-rio-guaire-debido-a-la-escasez-por-apagon-caracas- noticia-1185399

  6. The state of the internet in Venezuela Average download speeds: • 2.8 Mbps – SpeedTest State ISP dominant share of • residential internet access 1.5 Mbps – M_Lab Decreasing residential ~46% have residential • • internet access (OVSP) internet penetration Three mobile operators Fragile infrastructure and • • frequent blackouts

  7. Persecution of online speech

  8. INTERNET CENSORSHIP

  9. Clari fi cations Case One or more related sites or service being blocked for a speci fi c reason Event Continuous block of a target by an ISP

  10. Inde fi nite Blocks Long lasting, some 6+ years Telecom regulator orders On all/most mayor ISPs Big and small sites No clear end

  11. Tactical Inde fi nite Blocks Blocks Long lasting, some 6+ years As short as possible Telecom regulator orders Just in time to silence an event On all/most mayor ISPs Tries to balance the political cost Big and small sites of blocking high-tra ffi c sites and services No clear end Seen only at state ISP CANTV,

  12. How we measure A mixture of: • O ff the shell probes with custom settings • OONI (legacy CLI) • Custom scripts • OONI-run links with custom links • Occasionally RIPE ATLAS

  13. run.ooni.io links Fundamental to quickly get • multiple measurements fast Critical for unexpected incidents • Key to bridge any gaps • Faster turnaround of • measurements

  14. Measuring probes Guaranteed more data points of whole list • Increased test frequency based on URL importance • Alternative tests: • High intensity dns, tcp, fi ltering by http host and SNI • Block rate when needed • Currently migrating versions, to be released •

  15. ATLAS probes Alternative way to get di ff erent • kinds of measurements Record changes •

  16. 1.2.3.4 1.1.1.10 ¿ dominio.com ? dominio.com dominio.com: 1.2.3.4 Servidor DNS ISP

  17. DNS Blocks 1.2.3.4 1.1.1.10 ¿ dominio.com ? dominio.com dominio.com: … Servidor DNS ISP

  18. DNS Blocks On all mainstream ISPs CANTV, supercable, Domain Typical awnser Inter Digitel, Movistar no answer 104.28.8.75, (server 127.0.0.1 ntn24.com 104.28.9.75 failure)

  19. TCP blocks 1.2.3.4 Hello 1.1.1.10 1.1.1.10 dominio.com Address 1.1.1.10

  20. TCP blocks Was largely deprecated until • 2019 Mostly used to block Youtube • Evidence of miscon fi guration •

  21. HTTP blocks 1.2.3.4 Hello 1.1.1.10 : 1.1.1.10 I want dominio.com dominio.com Asking for domonio.com

  22. HTTP blocks (http host and SNI fi ltering) Higher value sites with inde fi nite • blocks Social media and streaming • platforms except YouTube most of the time Mostly used by CANTV •

  23. Evolution 2013 - 2018 Censorship moving depending on the priorities of the moment Focused on sites publishing black market exchange rates And News media around speci fi c events, specially protests Few large scale network shudowns

  24. Evolution 2018 Start of DPI blocking Mayor mainstream news targeted Block of Tor

  25. Evolution 2018 2019 Start of signi fi cant Dramatic increase of censorship to DPI blocking news Mayor mainstream Widespread use of SNI-Filtering news targeted Mayor internet platforms blocked Block of Tor Start of Tactical blocks

  26. Evolution 2018 2019 2020 Blocking of opposition Dramatic increase of Start of signi fi cant COVID-19 initiatives censorship to news DPI blocking Seemingly degraded DPI Widespread use of SNI-Filtering Mayor mainstream blocking capacity news targeted Mayor internet platforms Continuation of Tactical blocked Block of Tor blocks of mayor social media Start of Tactical blocks New blocks to news media

  27. Censorship of news media 12 news media sites just in the fi rst 3 • months of 2019 Over 25 news media sites blocked • International during 2019 36% National 64% 4 News sites newly blocked in 2020 • Severely limits access to • information

  28. Tactical blocks in 2019 Al least 64 Tactical blocks events • facebook 31 for YouTube 9% • instagram 13% Some times more than one in a • youtube 48% day twitter 13% AVG: 3h 08 min • periscope 17% MIN: 20min MAX: 24h

  29. ¿Damaged capacity? On 2020-04-06 a fi re disrupted a CANTV facility in Caracas • Multiple blocked sites became unblocked • Later Tactical blocks used DNS https://www.elnacional.com/venezuela/bomberos-controlaron-incendio-en-la-sede-de-cantv-del-municipio-chacao/

  30. Covid-19 blocks Dominio CANTV Movistar Digitel Supercable Inter Site Coronavirus Venezuela coronavirusvenezuela.info ACCESIBLE BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS ACCESIBLE Heroes de la Salud apoyosaludve.com BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS Heroes de la Salud heroesdesaludve.org * BLOQUEO DNS * BLOQUEO DNS * BLOQUEO DNS * BLOQUEO DNS BLOQUEO DNS Heroes de la Salud heroesdesaludve.info * BLOQUEO DNS * BLOQUEO DNS * BLOQUEO DNS * BLOQUEO DNS BLOQUEO DNS Heroes de la Salud porlasaludve.com BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS Heroes de la Salud saludvzla.com * BLOQUEO DNS * BLOQUEO DNS * BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS Heroes de la Salud apoyoheroesaludve.com BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS Teleconsulta COVID-19 teleconsulta.presidenciave.org ACCESIBLE BLOQUEO DNS BLOQUEO DNS ACCESIBLE ACCESIBLE Teleconsulta COVID-19 medicos.presidenciave.or ACCESIBLE BLOQUEO DNS ACCESIBLE ACCESIBLE ACCESIBLE Presidencia VE (J. Guaidó) presidenciave.com BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS ACCESIBLE Presidencia VE (J. Guaidó) presidenciave.org ACCESIBLE BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS Presidencia VE (J. Guaidó) pvenezuela.com BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS Presidencia VE (J. Guaidó) vepresidencia.com BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS BLOQUEO DNS Not current snapshot

  31. DNS MANIPULATION AND STATE-SPONSORED PHISHING

  32. Case: Voluntarios x Venezuela.com

  33. Vectors Malicious links to • voluntariovenezuela.com Visits to • voluntariosxvenezuela.com With poisoned / manipulated DNS responses

  34. First iteration Original: voluntarios x venezuela .com AWS Dominio en PublicDomainRegistry Malicioso: voluntariovenezuela .com 159.65.65.194 Digital Ocean Dominio registrado en GoDaddy

  35. Malicious links Twitter: Links to fake domain • being shared since 2019-02-11 Fake twitter accounts Twitter : • @voluntariosvene, vs @voluntariosxve Other channels •

  36. Malicious links Twitter: Promoción de links al • dominio falso desde la tarde del 11 de febrero Gente compartiendo el link falso • por distintos medios. Advertencias del navegador • reenforzaron el uso de links maliciosos

  37. DNS manipulation 1.2.3.4 1.1.1.10 ¿ dominio.com ? dominio.com dominio.com: 1.2.3.4 Middleboxes Servidor DNS

  38. DNS manipulation 1.1.1.10 1.2.3.4 Hello domino.com dominio.com dominio.com: 1.2.3.4 ISP Middleboxes Servidor DNS

  39. DNS manipulation 1.1.1.10 1.2.3.4 ¿ dominio.com ? dominio.com Middleboxes 8.8.8.8 Google’s Public DNS Servidor DNS

  40. DNS manipulation 1.1.1.10 1.2.3.4 ¿ dominio.com ? dominio.com dominio.com: 1.2.3.4 Middleboxes 8.8.8.8 Google’s Public DNS Servidor DNS

  41. DNS manipulation 1.1.1.10 1.2.3.4 ¿ dominio.com ? dominio.com dominio.com: dominio.com: 1.2.3.4 1.1.1.10 Middleboxes 8.8.8.8 Google’s Public DNS Servidor DNS

  42. DNS manipulation 1.1.1.10 1.2.3.4 ¿ dominio.com ? dominio.com dominio.com: dominio.com: 1.1.1.10 1.2.3.4 Middleboxes 8.8.8.8 Google’s Public DNS Servidor DNS

  43. DNS manipulation 1.1.1.10 1.2.3.4 Hello domino.com dominio.com dominio.com: 1.2.3.4 Middleboxes 8.8.8.8 Google’s Public DNS Servidor DNS

  44. Fuel for fake news

  45. Personal information published

  46. Exposure for 5 thousand victims

  47. More domains • m.facebook.co.ve • outlook.live.web.ve • www.facebook.co.ve • live.web.ve • static.facebook.co.ve • www.live.web.ve • facebook.co.ve • login.live.web.ve • ssl.gmail.web.ve • twitter.info.ve • gmail.web.ve • mobile.twitter.info.ve • www.gmail.web.ve • api.twitter.info.ve • accounts.gmail.web.ve • abs.twitter.info.ve • linkedin.co.ve • www.voluntariovenezuela.com • www.linkedin.co.ve • voluntariovenezuela.com • account.live.web.ve

  48. Example: accounts.gmail.com source: checkphish.ai

  49. Inconsistent DNS responses documented OONI mobile app • run.ooni.io Package capture of manual • experiments

  50. Case: Héroes de la salud

  51. Case: Héroes de la salud

  52. Selectively (not) blocking 2020-04-30

  53. Similar M.O.

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