US Cellular data leak Dec-2021
darkleakmarketThis record tracks a ransomware attack claimed by the darkleakmarket group against US Cellular data leak Dec-2021. It collects the publicly disclosed attack details — sector, location and timeline — as published on the operator's leak site and indexed by Breach House.
Window Zero
EXPOSURE GAPWindow Zero is the time the breach stayed in the open before anyone said so — the gap between when the attack was first discovered on the operator's leak site (t1) and when it was publicly disclosed (t2). The wider this window, the longer victims, staff and customers were exposed with no warning.
Attack Summary
UScellular is a U.S.-based wireless telecommunications company in the Other sector that provides mobile voice, data, and related account services to consumer and business customers. In December 2021, reporting on the incident described unauthorized access to its billing system and wireless customer account data, with disclosures focused on account information rather than a confirmed broader compromise. The December 2021 leak listing should be read as a threat-intelligence record for this entity and incident context. It was listed as a ransomware victim associated with darkleakmarket.
Leak Screenshots
SAMPLEProof-of-breach screenshots the operator posted from the stolen data. Previews are redacted and locked — the originals are available on HaveIBeenRansom.