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KREBS+KIEFER

listed as kuk.de / KREBS + KIEFER / 500GB · Claimed by Revil · listed 5 years ago

58m
Age
since listed · data leaked

Status timeline

  1. ListedSep 9, 2021
  2. Data leakeddate unknown

At a glance

Group
Revil
Status
Data leaked
Country
Germany
Sector
Business Services
Listed on leak site
Sep 9, 2021

About the victim

AI dossier — public-source company profile

KREBS+KIEFER is a German engineering consultancy founded in 1950, employing approximately 800 staff across 16 locations. The firm offers interdisciplinary services spanning construction management, structural engineering, geotechnics, fire protection, traffic infrastructure, hydraulic engineering, and building physics. It operates across regional and international markets with a focus on planning, expert assessment, and project management.

Industry
Civil & Structural Engineering Consulting
Employees
800
Founded
1950

Attack summary

Severity: high — 500 GB of data is claimed exfiltrated and published (disclosed status: data_published) from an ~800-employee engineering consultancy handling critical infrastructure projects; likely includes project documentation, employee PII, and potentially sensitive infrastructure design data.

REvil claims to have exfiltrated approximately 500 GB of data from KREBS+KIEFER and has published the data, though no specific data categories are detailed in the captured post.

high

Data the group says was taken

AI dossier — extracted from the leak post
  • 500 GB of company data (unspecified contents)

Sources

Source

Indexed 5 years ago

This page surfaces a public ransomware disclosure indexed by Darkfield. Original posts come from the operator's own leak site; we cross-check against ransomware.live, RansomLook and RansomWatch where applicable. Share this URL freely.

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Disclosure context

About Revil

REvil, also known as Sodinokibi, was a highly sophisticated ransomware-as-a-service operation that emerged in April 2019 and quickly became one of the most prolific and financially successful cybercriminal organizations, primarily motivated by financial gain. The group is believed to have originated from Russia, operating as a RaaS model where core developers rented their ransomware tools to affiliate criminals, and maintained connections to the now-defunct GandCrab ransomware operation with some researchers suggesting personnel overlap. REvil primarily gained initial access through exploiting vulnerabilities in remote desktop protocol implementations, phishing campaigns, and supply chain attacks, employing double extortion tactics where they exfiltrated sensitive data before encryption and threatened to publish it on their "Happy Blog" leak site if ransoms were not paid, using advanced encryption methods that made file recovery nearly impossible without payment. The group conducted several high-profile attacks including the devastating supply chain attack against Kaseya in July 2021 that affected thousands of downstream customers, attacks on major corporations like JBS Foods, and demanded ransoms reaching up to $70 million, ultimately leading to increased law enforcement attention and pressure from international authorities. Following coordinated law enforcement actions and mounting pressure from the U.S. and Russian governments in late 2021, REvil's infrastructure was taken down and the group ceased operations, with several suspected members reportedly arrested by Russian authorities. The group has been linked to 96 public disclosures across our corpus. First observed on a leak site on August 26, 2019; most recent post November 28, 2022. The operation is currently inactive.

Also tracked as: Sodinokibi.

Timeline of this disclosure

  • September 9, 2021kuk.de / KREBS + KIEFER / 500GB listed by Revilon the group's public leak site

Other recent disclosures by Revil

Revil has been linked to 96 public victims on Darkfield. A sample of the most recent:

See the full Revil dossier →

Sector and geography

This disclosure adds to ransomware activity in the Business Services sector, which has 3,796 disclosures indexed across all operators we track. Geographically, kuk.de / KREBS + KIEFER / 500GB is reported in Germany, a country with 926 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Revil means kuk.de / KREBS + KIEFER / 500GB 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, CERT-Bund (Germany), as required for your jurisdiction.
  • Monitor for the data appearing on Revil'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.