**Nozelesn** is an obscure ransomware group that first emerged in December 2018 with apparent financial motivations, though limited public documentation exists about their operations. The group's origin and affiliations remain largely unknown, with no confirmed country of origin or established links to other ransomware families documented by major security firms or law enforcement agencies. Their attack methodology and technical capabilities are not well-documented in public threat intelligence reports, with no detailed analysis available from CISA, FBI, or prominent security researchers regarding their initial access vectors, encryption methods, or whether they employ data exfiltration tactics. Based on available data, the group has targeted at least one victim in the United States government facilities sector, though no major high-profile campaigns or significant ransoms have been publicly reported by security researchers. The current operational status of nozelesn remains unclear due to the limited intelligence available about this group's activities beyond their initial emergence period. The group has been linked to 1 public disclosures across our corpus. First observed on a leak site on December 17, 2018. The operation is currently inactive.
Sector and geography
This disclosure adds to ransomware activity in the Government Facilities sector, which has 88 disclosures indexed across all operators we track. Geographically, Town of Jupiter is reported in United States, a country with 11,033 ransomware disclosures in our corpus.
If your organisation is affected
A listing by nozelesn means Town of Jupiter 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.
- Report the incident to your national CERT, CISA (United States), as required for your jurisdiction.
- Monitor for the data appearing on nozelesn'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.
