Prolock is a ransomware group that emerged in February 2020, operating with primarily financial motivations through targeted attacks against organizations in the United States. The group's origin and potential affiliations remain largely undocumented in public threat intelligence reporting, with limited information available about whether they operate as an independent entity or utilize a ransomware-as-a-service model. Based on available data, Prolock has demonstrated a targeting preference for financial institutions and government facilities, though detailed information about their specific attack methodologies, initial access vectors, and encryption techniques has not been extensively documented by major security research organizations. The group has maintained a relatively low profile compared to other ransomware operations, with only two publicly documented victims, suggesting either limited operational scope or successful operational security that has kept many of their activities from public disclosure. Current intelligence indicates that Prolock's operational status remains unclear, with insufficient public documentation from major threat intelligence sources to definitively assess whether the group remains active, has ceased operations, or potentially rebranded under a different identity. The group has been linked to 2 public disclosures across our corpus. First observed on a leak site on February 23, 2020; most recent post April 25, 2020. 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, LaSalle County Government is reported in United States, a country with 11,033 ransomware disclosures in our corpus.
If your organisation is affected
A listing by Prolock means LaSalle County Government 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 Prolock'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.
