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Ransomware Victim Technology

ARM

Ransomware attack by D1r · Disclosed July 13, 2026 · 🇬🇧 United Kingdom

arm.com

Date Disclosed
Jul 13, 2026
2026
Threat Group
D1r
3 total victims
Country
🇬🇧 United Kingdom
Industry
Technology

ThreatAI Analysis

Compiled from this incident record and the threat intelligence profile for D1r. Figures and technique mappings are quoted from the source data, not inferred.

About the D1r group

D1R Claims Synopsys and Bosch Breaches, but Synopsys Disputes Intrusion D1r has listed 3 victims since July 2026.

How D1r is documented to operate

Valid Accounts T1078 Stealth Persistence

Adversaries may obtain and abuse credentials of existing accounts as a means of gaining Initial Access, Persistence, Privilege Escalation, or Defense Evasion. Compromised credentials may be used to bypass access controls placed on various resources on systems within the network and may even be used for persistent access to remote systems and externally available services, such as VPNs, Outlook Web Access, network devices, and remote desktop. Compromised credentials may also grant an adversary increased privilege to specific systems or access to restricted areas of the network.

Mitigations: Application Developer Guidance, User Training, Password Policies, User Account Management, Privileged Account Management, Multi-factor Authentication

MITRE ATT&CK reference →
Exploit Public-Facing Application T1190 Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network. The weakness in the system can be a software bug, a temporary glitch, or a misconfiguration. Exploited applications are often websites/web servers, but can also include databases (like SQL), standard services (like SMB or SSH), network device administration and management protocols (like SNMP and Smart Install), and any other system with Internet-accessible open sockets. On ESXi infrastructure, adversaries may exploit exposed OpenSLP services; they may alternatively exploit exposed VMware vCenter servers.

Mitigations: Vulnerability Scanning, Limit Access to Resource Over Network, Filter Network Traffic, Network Segmentation, Privileged Account Management, Application Isolation and Sandboxing

MITRE ATT&CK reference →
Multi-Factor Authentication Interception T1111 Credential Access

Adversaries may target multi-factor authentication (MFA) mechanisms, (i.e., smart cards, token generators, etc.) to gain access to credentials that can be used to access systems, services, and network resources. Use of MFA is recommended and provides a higher level of security than usernames and passwords alone, but organizations should be aware of techniques that could be used to intercept and bypass these security mechanisms. If a smart card is used for multi-factor authentication, then a keylogger will need to be used to obtain the password associated with a smart card during normal use.

Mitigations: User Training

MITRE ATT&CK reference →
Steal or Forge Authentication Certificates T1649 Credential Access

Adversaries may steal or forge certificates used for authentication to access remote systems or resources. Digital certificates are often used to sign and encrypt messages and/or files. Certificates are also used as authentication material. For example, Entra ID device certificates and Active Directory Certificate Services (AD CS) certificates bind to an identity and can be used as credentials for domain accounts. Authentication certificates can be both stolen and forged. For example, AD CS certificates can be stolen from encrypted storage (in the Registry or files), misplaced certificate files (i.e.

Mitigations: Audit, Active Directory Configuration, Disable or Remove Feature or Program, Encrypt Sensitive Information

MITRE ATT&CK reference →
Data from Information Repositories T1213 Collection

Adversaries may leverage information repositories to mine valuable information. Information repositories are tools that allow for storage of information, typically to facilitate collaboration or information sharing between users, and can store a wide variety of data that may aid adversaries in further objectives, such as Credential Access, Lateral Movement, or Defense Evasion, or direct access to the target information. Adversaries may also abuse external sharing features to share sensitive documents with recipients outside of the organization (i.e., Transfer Data to Cloud Account).

Mitigations: User Training, Out-of-Band Communications Channel, User Account Management, Multi-factor Authentication, Software Configuration, Audit

MITRE ATT&CK reference →
Data from Cloud Storage T1530 Collection

Adversaries may access data from cloud storage. Many IaaS providers offer solutions for online data object storage such as Amazon S3, Azure Storage, and Google Cloud Storage. Similarly, SaaS enterprise platforms such as Office 365 and Google Workspace provide cloud-based document storage to users through services such as OneDrive and Google Drive, while SaaS application providers such as Slack, Confluence, Salesforce, and Dropbox may provide cloud storage solutions as a peripheral or primary use case of their platform.

Mitigations: Filter Network Traffic, User Account Management, Restrict File and Directory Permissions, Multi-factor Authentication, Audit, Encrypt Sensitive Information

MITRE ATT&CK reference →

MITRE ATT&CK techniques attributed to D1r across its recorded activity, not a finding about how ARM was reached.

Incident Analysis

ARM was targeted by D1r ransomware, one of the most active ransomware groups in our database with 3 confirmed victims globally. The attack was disclosed on July 13, 2026, when ARM appeared on the group's dark web leak site.

ARM is based in United Kingdom , operating in the Technology sector. United Kingdom ranks #4 globally for ransomware attacks, with 894 victims in our database.

Sector context: Technology companies hold intellectual property, customer data, and source code — all highly valuable assets. A successful ransomware attack can also put downstream customers at risk through supply chain exposure.

D1r typically employs a double extortion model: first exfiltrating sensitive data from the victim's systems, then deploying ransomware to encrypt files. Victims face two simultaneous threats — paying to restore access and paying to prevent publication of stolen data. The group's leak site publishes victim names and exfiltrated data as leverage.

Data source: This incident record is sourced from public ransomware group leak site disclosures aggregated via the ransomware.live API. Disclosure date reflects when the victim was published on the leak site, which may differ from the initial date of compromise. This platform does not publish or link to stolen data. Last data update: Sep 7, 2026 14:00 UTC.

Frequently Asked Questions

Was ARM attacked by ransomware?

Yes. ARM was listed as a victim of the D1r ransomware group on July 13, 2026. The organisation is based in United Kingdom and operates in the Technology sector. The disclosure appeared on the group's dark web leak site.

Which ransomware group attacked ARM?

ARM was attacked by D1r ransomware. D1r is one of the most active ransomware groups, having claimed 3 victims globally. The group typically employs a double-extortion model: encrypting the victim's files and threatening to publish stolen data.

When did the ARM ransomware attack occur?

The ransomware attack on ARM was disclosed on July 13, 2026. This date reflects when the victim was published on the threat group's leak site, which may differ from the actual date of initial compromise.

What data was stolen in the ARM ransomware attack?

The specific data stolen from ARM has not been independently verified by this platform. Ransomware groups typically exfiltrate data before encrypting systems and use the threat of publication to pressure victims. As a Technology organisation, ARM likely held source code, intellectual property, and customer data.

How can organisations protect against D1r attacks?

To defend against D1r and similar threat actors, organisations should: maintain regular offline backups tested for restoration; implement network segmentation to limit lateral movement; deploy multi-factor authentication on all remote access; use endpoint detection and response (EDR) tools; conduct regular phishing and security awareness training; and monitor threat intelligence feeds for indicators of compromise (IOCs) associated with active groups.