Underground is a ransomware operator no longer publishing new disclosures. Darkfield has indexed 26 public victims claimed by this operator between May 1, 2024 and August 15, 2025. Underground is a relatively new ransomware group that emerged in May 2024, primarily motivated by financial gain through extortion operations targeting organizations across multiple sectors. The group's origin and affiliations remain largely undocumented in public threat intelligence reporting, with no confirmed details about their country of origin or whether they operate as an independent entity or through a Ransomware-as-a-Service model. Based on the limited public information available, Underground has demonstrated a preference for targeting technology, healthcare, business services, manufacturing, and agriculture sectors, with their attacks concentrated primarily in the United States, Canada, South Korea, Germany, and Taiwan. The group's specific attack methodologies, initial access vectors, and technical capabilities have not been extensively documented in publicly available threat intelligence reports from major security firms or government agencies. With only 26 known victims since their emergence in May 2024, Underground represents a smaller-scale operation compared to established ransomware groups, though their cross-sector targeting approach indicates opportunistic victim selection rather than specialized industry focus. Given the recent emergence of this group and limited public reporting, Underground appears to remain active but operates at a relatively low profile compared to more established ransomware families.
How we know this. Operator profiles on Darkfield are built from continuous monitoring of every leak site the group is known to operate, cross-correlated with community-curated feeds (RansomLook, ransomware.live, RansomWatch, MISP-galaxy). Status flips from active to inactive when no new disclosure appears for 60 days. MITRE ATT&CK mappings shown in the interactive section below are sourced from CISA, vendor analysis, and the MITRE community catalog — we attribute each technique back to its source. Aliases reflect operator re-brands and affiliate splits.