DarkSide is a financially motivated ransomware group that emerged in August 2020, quickly gaining notoriety for its professional operational structure and targeted attacks against high-value organizations. The group is widely assessed by Mandiant, CISA, and the FBI to be based in Russia or a Russian-speaking country, and operated as a Ransomware-as-a-Service (RaaS) platform, recruiting affiliates to conduct intrusions while the core group maintained the malware infrastructure and negotiation portals. DarkSide primarily gained initial access through compromised Remote Desktop Protocol (RDP) credentials, phishing, and exploitation of vulnerable internet-facing systems, subsequently deploying tools such as Cobalt Strike and Mimikatz for lateral movement and credential harvesting before exfiltrating sensitive data and encrypting victim systems in a double extortion scheme. The group's most significant and publicly documented campaign was the May 2021 attack against Colonial Pipeline, a critical U.S. fuel pipeline operator, which caused widespread fuel supply disruptions across the U.S. East Coast, prompted a CISA and FBI joint advisory, and resulted in a ransom payment of approximately 4.4 million USD, of which the U.S. Department of Justice subsequently recovered roughly 2.3 million USD. Following the Colonial Pipeline attack and the significant law enforcement and geopolitical pressure it generated, DarkSide announced it was shutting down operations in May 2021, citing pressure from an unspecified third party, though security researchers including Mandiant assessed that the group likely rebranded as BlackMatter shortly thereafter before that successor group also ceased operations in late 2021. The group has been linked to 10 public disclosures across our corpus. First observed on a leak site on August 1, 2020; most recent post May 13, 2021. The operation is currently inactive.
Also tracked as: BlackMatter.
Sector and geography
This disclosure adds to ransomware activity in the Transportation/Logistics sector, which has 1,081 disclosures indexed across all operators we track. Geographically, Discount Car and Truck Rentals is reported in Canada, a country with 316 ransomware disclosures in our corpus.
If your organisation is affected
A listing by darkside means Discount Car and Truck Rentals 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, CCCS (Canada), as required for your jurisdiction.
- Monitor for the data appearing on darkside'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.
