Was Kelly Group hit by ransomware?

Kelly Group was listed by the Blackbyte ransomware operation (United Kingdom), and stolen data was published on the group's leak site. Darkfield tracks this disclosure with the original leak post, screenshot and group context.

Who is the Blackbyte ransomware group?

Blackbyte is a ransomware operator tracked by Darkfield. See the full operator dossier for its known victims, sectors targeted, IOCs and leak-site infrastructure.

What data was leaked in the Kelly Group breach?

Blackbyte published data attributed to Kelly Group. Darkfield captured the leak post and a screenshot of the listing.

Ransomware victim disclosure

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Kelly Group

Claimed by Blackbyte · listed 3 years ago

40m

Age

since listed · data leaked

Status timeline

ListedMar 20, 2023
Data leakeddate unknown

At a glance

Group: Blackbyte
Status: Data leaked
Country: United Kingdom
Sector: Telecommunications
Listed on leak site: Mar 20, 2023

About the victim

AI dossier — public-source company profile

Kelly Group is a UK-based network infrastructure services company founded in 1985, originally established to support the emerging cable television market. The company has grown to provide end-to-end telecommunications, broadband, rail, civils, utilities, fleet, and traffic management services across the UK and Ireland. It operates with a workforce of approximately 5,000 employees, over 40 national operational centres, and a fleet of more than 3,800 vehicles.

Industry: Telecommunications & Utility Network Installation
Address: United Kingdom
Employees: 5000
Founded: 1985

Attack summary

Severity: high — Data has been published by the ransomware group against a large (~5,000 employee) critical national infrastructure-adjacent company operating in telecommunications and utility network installation, indicating confirmed exfiltration of significant business data with potential exposure of employee and client records.

Blackbyte claims to have attacked Kelly Group and has published data ('data_published' status), indicating exfiltration of company data. No ransom amount or specific data volume has been stated in the post.

high

Data the group says was taken

AI dossier — extracted from the leak post

Company operational data
Employee records
Client information
Engineering/network project data

What the group claims

Kelly Group has been at the forefront of the telecommunications industry for more than 35 years, installing the very first customer cable television service on 17th September 1985.Established to support the emerging UK cable television market, Kelly Group has grown and diversified to meet the needs of our clients and their customers.

Sources

Victim sitekelly.co.uk/

Source

Indexed 3 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 Blackbyte

BlackByte is a ransomware-as-a-service (RaaS) operation that emerged in October 2021, primarily motivated by financial gain through double extortion tactics targeting organizations across multiple sectors. The group is suspected to operate from Russia or former Soviet states based on their use of Russian-language forums and avoidance of targeting organizations in Commonwealth of Independent States countries, though they maintain no confirmed links to other established ransomware families. BlackByte operators typically gain initial access through vulnerable Microsoft Exchange servers, phishing campaigns, and exploitation of remote desktop protocol (RDP) services, employing tools such as Cobalt Strike for lateral movement and data exfiltration before deploying their custom ransomware payload that uses AES-256 encryption with RSA-2048 key protection. The group has demonstrated particular focus on critical infrastructure sectors, with the FBI and CISA issuing joint advisories in February 2022 highlighting attacks against organizations in government, healthcare, manufacturing, and education sectors, including notable incidents affecting San Francisco's transportation authority and multiple healthcare systems across the United States. BlackByte remains active as of 2024, continuing to evolve their tactics and maintain their leak site for publishing stolen data from victims who refuse to pay ransoms. The group has been linked to 147 public disclosures across our corpus. First observed on a leak site on October 4, 2021; most recent post July 30, 2025. The operation is currently inactive.

Timeline of this disclosure

March 20, 2023Kelly Group listed by Blackbyteon the group's public leak site

Other recent disclosures by Blackbyte

Blackbyte has been linked to 147 public victims on Darkfield. A sample of the most recent:

See the full Blackbyte dossier →

Sector and geography

This disclosure adds to ransomware activity in the Telecommunications sector, which has 87 disclosures indexed across all operators we track. Geographically, Kelly Group is reported in United Kingdom, a country with 1,217 ransomware disclosures in our corpus.

If your organisation is affected

A listing by Blackbyte means Kelly Group 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, NCSC (United Kingdom), as required for your jurisdiction.
Monitor for the data appearing on Blackbyte'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.