Optus — Cyber Attacks, Breaches & Threat Activity

Threat entity extracted from intelligence sources

Frequency
13
occurrences
First Seen
November 18, 2025
Last Seen
June 18, 2026

Optus is a organization tracked across 11 threat clusters and 13 intelligence report mentions on ThreatCluster. First observed November 18, 2025; most recent activity June 18, 2026.

Overview

Optus is a major Australian telecommunications company (subsidiary of Singtel) that provides mobile, internet, and related services. Its large customer data footprint and history of data breaches place it at the forefront of Australia's cybersecurity risk landscape, influencing regulatory focus and threat intelligence around data protection and identity fraud.

Related Threat Clusters

  • Optus Privacy Breach Affects 51,000 Customers

    Optus has been found to have breached the privacy of 51,000 customers by mistakenly publishing their unlisted phone numbers in the White Pages directory. This breach, which occurred between 2015 and 2019, was a result…

    3 articles · Updated June 11, 2026
  • Growing Legal Complexity in Cybersecurity and AI Governance

    Recent developments in cybersecurity law highlight a significant shift towards stricter enforcement and legal complexity, particularly in Australia. The Federal Court's decision in Medibank Private Limited v McClure…

    4 articles · Updated June 18, 2026
  • Australia Establishes Cyber Incident Review Board Following Major Breaches

    Australia has launched a Cyber Incident Review Board to enhance its cybersecurity response following significant breaches, including attacks on Medibank and Optus. This board, established under the Cyber Security Act…

    5 articles · Updated May 6, 2026
  • Optus Data-Breach Class Gains Intervention Rights in Watchdog Case

    A class of individuals affected by the Optus data breach has been granted permission to intervene in a case brought by the Australian watchdog. This legal development allows the class to present their interests and…

    2 articles · Updated June 4, 2026
  • Optus Ransomware Incident Linked to Singaporean Payment

    In March 2026, Australian officials suspect that Optus, owned by a Singaporean company, made an undisclosed payment to resolve a ransomware attack that compromised sensitive data. The breach, which occurred in 2022,…

    1 article · Updated March 11, 2026
  • Services Australia Seeks Enhanced Authority Amid Surge in Data Breaches

    Services Australia is set to gain new powers to compel third-party organizations to promptly disclose data breaches involving government identifiers. The agency reported a significant increase in notifiable data…

    2 articles · Updated December 11, 2025
  • Singapore Telcos Targeted by UNC3886 Cyberattack

    In July 2025, an advanced persistent threat actor known as UNC3886 targeted Singapore's four telecommunications companies, compromising critical infrastructure. The attack was detected by the Infocomm Media Development…

    78 articles · Updated February 9, 2026
  • Samsung Handset Failure Leads to Fatal Emergency Call Incident in Australia

    A Sydney resident died after their Samsung handset failed to connect to 000, Australia's emergency number. TPG Telecom confirmed the incident, which involved a customer using a Lebara-branded service, occurred after…

    2 articles · Updated November 18, 2025
  • Rise of AI-Driven Social Engineering Attacks

    Social engineering attacks, including phishing, smishing, and vishing, have become increasingly sophisticated, leveraging AI to manipulate trust rather than breaching firewalls. These methods have turned communication…

    11 articles · Updated November 18, 2025
  • Samsung Handset Failure Leads to Fatal Emergency Call Incident in Australia

    A Sydney resident died after their Samsung handset failed to connect to 000, Australia's emergency number. TPG Telecom confirmed the incident occurred after the customer, using a Lebara-branded service, was unable to…

    2 articles · Updated November 18, 2025

Recent Intelligence Reports

  • Digital Governance, Cyber and Privacy | Quarterly Roundup — Cbp.Au · June 18, 2026
  • Optus failed to protect data in White Pages breach, privacy watchdog says — Lawyerly.Au · June 11, 2026
  • Optus Data Breach — www.mauriceblackburn.com.au · June 11, 2026
  • Marathon OAIC investigation finds Optus breached 51,000 customers' privacy — Itnews.Au · June 11, 2026
  • Optus data-breach class allowed to intervene in Australian watchdog's case — Mlex · June 4, 2026
  • Optus data-breach class allowed to intervene in Australian watchdog's case — Mlex · June 4, 2026
  • Australia Forms Cyber Incident Review Board to Strengthen Defences After Major Breaches — Thecyberexpress · May 6, 2026
  • Australian officials suspect Singaporean company paid Optus ransomware after massive ... — Thewest.Au · March 11, 2026

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