Active Incident
Confirmed: historical blocking: CN 2023-01-01 to 2023-07-09
China · January 1, 2023 · 190 days
Backfilled from OONI historical archive. 186 anomalous day(s), 684 measurements, 91% anomaly rate. Signal types: block, interference. Signal levels: critical.
Evidence
91%
Anomaly Rate
684
Measurements
99%
Confidence
What This Means
91% of 684 network tests from China failed to reach these services. Global baseline failure rate is typically 1-3%. This 88+ percentage point difference strongly indicates intentional blocking.
How We Detected This
Data Sourceooni-historical-backfill
ML ModelGradientBoosting v3.3 (LOCO median F1 0.87, honest across 127 countries)
Confidence Score99% certainty of censorship
Detection TimeJanuary 1, 2023
What we cannot say
- Who caused it — measurement data alone does not attribute this to any government, ISP, or other actor.
- Intent — anomalous or unreachable measurements indicate interference, not a stated motive or a deliberate-vs-incidental determination.
- Which networks — no specific ASN/ISP is identified for this incident.
- The mechanism — we cannot state whether this was DNS tampering, TLS/SNI reset, an HTTP blockpage, throttling, or an infrastructure outage.
- Sub-national scope — measurement is aggregated at the country level; we cannot localize to a province, city, or network segment.
- Independent corroboration — this rests on a single source; treat it as a single-source signal, not a multi-source confirmation.
Cite This Incident
Voidly Research. (2023). Confirmed: historical blocking: CN 2023-01-01 to 2023-07-09 [CN-2023-0535]. Voidly Global Censorship Index. https://voidly.ai/incident/CN-2023-0535
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