Majinahanashi is an emerging ransomware group first observed in August 2026 with an apparent financial motivation, having claimed at least 12 victims across multiple continents in a relatively short operational window. At the time of this profile, no authoritative public attribution has been established by CISA, the FBI, Mandiant, or other reputable security research organizations regarding the group's country of origin, affiliations with known threat actor clusters, or whether it operates under a Ransomware-as-a-Service model or as an independent closed group. Based on available victimology data, the group has demonstrated a geographically diverse targeting pattern spanning Italy, the United States, Portugal, Switzerland, and Colombia, suggesting either a broad opportunistic approach or the use of affiliate infrastructure with varied regional reach. Targeted sectors include manufacturing, retail and e-commerce, healthcare, and technology, alongside victims whose sector classification remains unattributed, a distribution consistent with financially motivated actors prioritizing vulnerable or high-value targets over ideological selection criteria. No specific tools, initial access vectors, encryption methodologies, or extortion tactics have been publicly documented for this group by authoritative sources at this time, and no notable high-profile campaigns, record ransom demands, or law enforcement actions against the group have been publicly reported. Majinahanashi should be considered an active and developing threat given its recent emergence, and organizations in its targeted geographies and sectors are advised to monitor credible threat intelligence channels for updated attribution and technical indicators as reporting matures. The group has been linked to 15 public disclosures across our corpus. First observed on a leak site on August 12, 2026; most recent post August 16, 2026. The operation is currently active.
Sector and geography
This disclosure adds to ransomware activity in the Energy & Utilities sector, which has 168 disclosures indexed across all operators we track. Geographically, CALICHE is reported in Chile, a country with 7 ransomware disclosures in our corpus.
If your organisation is affected
A listing by majinahanashi means CALICHE appeared on a ransomware extortion site and data attributed to it has been published. If this is your organisation, or a supplier you depend on, the priority is to confirm the intrusion and contain it before the window to act closes.
- Engage your incident-response team and preserve forensic evidence before remediating — do not wipe affected systems first.
- Force a password reset and revoke active sessions for exposed accounts; rotate any credentials, API keys or certificates that may have been in the stolen data.
- Assess regulatory notification duties (GDPR, NIS2, sector regulators) — many carry a 72-hour reporting clock from awareness.
- Monitor for the data appearing on majinahanashi's leak site and across paste and breach channels, and brief downstream partners who may be exposed through you.
How we know this. Darkfield monitors public ransomware leak sites continuously, archiving every new disclosure and the data later released against the victim. Each entry on this page is sourced from the operator's own publication and cross-checked against complementary OSINT feeds (RansomLook, ransomware.live, RansomWatch). We do not collect or host stolen data — only the metadata, timestamps and screenshots needed to make the public disclosure searchable and accountable. Records here are corrected when the original post is edited, retracted, or merged with another disclosure.
