HDDCryptor is an obscure ransomware variant that emerged in November 2016, primarily motivated by financial gain through targeted encryption attacks. The group's origin and affiliations remain largely undocumented in public threat intelligence reporting, with limited information available about their operational structure or ties to other cybercriminal organizations. Based on available incident data, HDDCryptor appears to have conducted targeted attacks with a specific focus on transportation systems infrastructure within the United States, though their exact initial access vectors and technical methodologies have not been extensively documented by major security research firms. The group's operational footprint appears minimal, with only one publicly documented victim case, suggesting either highly selective targeting or limited operational scope compared to more prolific ransomware families. Current intelligence indicates HDDCryptor has remained largely inactive or dormant since its initial observation period, with no significant campaigns or law enforcement actions publicly reported against the operators. The group has been linked to 2 public disclosures across our corpus. First observed on a leak site on November 25, 2016; most recent post May 7, 2020. The operation is currently inactive.
Also tracked as: Mamba.
Sector and geography
This disclosure adds to ransomware activity in the Transportation Systems sector, which has 28 disclosures indexed across all operators we track. Geographically, San Francisco Municipal Transport Authority (SFMTA) is reported in United States, a country with 11,033 ransomware disclosures in our corpus.
If your organisation is affected
A listing by hddcryptor means San Francisco Municipal Transport Authority (SFMTA) 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 hddcryptor'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.
