Advanced persistent threats (APTs) are the ‘slow‑burn’ of the cyber world. These well‑funded, highly skilled groups plan their attacks over weeks or months, moving patiently through a network to gather credentials, and waiting for the perfect moment to strike.
When an APT decides to probe a New Zealand organisation, the potential impact can be severe:
- data could be exfiltrated,
- critical systems disabled, or
- even sabotage carried out.
This article describes how a sophisticated APT attempted to infiltrate a local organisation, and how the NCSC partnered with a commercial cyber‑security provider to respond. It will also explain why, despite the seriousness of the threat, the outcome was contained. We also discuss the steps any organisation can take to guard against a similar attack.
Threat detection and assessment
Earlier this year, an organisation informed the NCSC that unauthorised activity had been detected on their network, and they requested assistance.
The NCSC then opened an investigation and began to work in tandem with a commercial cyber security provider to assess the threat and determine how it should be contained.
Deep forensic analysis, log reviews and threat‑intel correlation were carried out, and both teams concluded that the activity originated from a resourceful, sophisticated threat actor that could be classified as an advanced persistent threat (APT).
The commercial provider then mapped the scope of the compromise and gave the impacted organisation concrete advice on how to stop the intrusion from spreading.
Using our own unique capabilities, the NCSC verified that no data had been stolen and offered further guidance on mitigating any lingering risk.
The importance of being prepared
With the immediate danger neutralised, the NCSC examined why the threat actors failed to achieve their likely goals. The review showed that the organisation’s existing cyber security hygiene had been decisive in stopping the APT.
This included:
- strong passwords,
- multi‑factor authentication (MFA), and
- network segmentation.
The goal of the threat actor in this incident remains unknown, but one of the main reasons they were not able to steal data is that good cyber security practices were already in place. Being prepared for an incident is crucial in helping to lessen its impact and recovering quickly.
Positive collaboration
The swift response was only possible because three parties worked together.
The impacted organisation promptly reported the anomaly and followed its own incident response procedures.
The commercial cyber security provider brought:
- deep technical expertise,
- performed on‑site forensics, and
- helped to contain the breach.
The NCSC contributed:
- specialised digital forensics and intelligence capabilities,
- validated that no data exfiltration occurred, and
- produced a set of recommendations for the future.
This partnership illustrates how public‑sector expertise and private‑sector capabilities can combine to neutralise even the most advanced adversaries.
Following the incident, the NCSC made a number of tactical and strategic security recommendations to the impacted organisation. It should be noted that the organisation in this case had already implemented many of these measures, which helped to limit the extent of the attack.
Tactical recommendations
- If unauthorised activity is detected, organisations should reset all credentials within the environment, including all user accounts, service accounts, and local administrative credentials associated with known compromised hosts. Privileged accounts and known compromised accounts should be prioritised for credential resets.
- Organisations should consider implementing and enforcing password complexity and multi-factor authentication (MFA) requirements across all accounts.
- Restrict the ability of service accounts to access other devices over the network, in order to limit the ability for compromised service accounts to be utilised for lateral movement.
- Where secure socket layer (SSL) virtual private networks (VPNs) are used, ensure multi-factor authentication is required and consider limiting access to trusted IP ranges.
Strategic recommendations
The NCSC’s strategic recommendations are organised according to the functions of the NCSC cyber security framework.
Prevent and Protect
- Organisations should ensure all internet-facing services are included in regular patching cycles and running the latest security updates.
- Remove or limit access to on-premises Exchange servers and any other services that do not support modern authentication.
Detect and Contain
- Ensure alerting for security products is actively monitored for triage and remediation.
- Consider forwarding firewall logs from internet gateways to a SIEM and retaining for a period sufficient to allow a retrospective incident investigation.
- Limit the opportunity for data exfiltration and command and control traffic by restricting outbound internet access from servers to required services only.
Key takeaways
APT activity is real and can target any organisation. The threat actor in this case was sophisticated, but the breach never escalated because of solid defensive layers.
Speed and coordination proved decisive, including:
- prompt reporting to the NCSC,
- immediate credential resets, and
- a joint effort with a commercial security partner contained the incident quickly.
Good security hygiene stopped data loss in its tracks, including:
- Multi-factor authentication,
- strong password policies,
- network segmentation, and
- diligent monitoring.
Ongoing improvement is essential — the tactical and strategic recommendations should be treated as a roadmap rather than a one‑off checklist.
By internalising these lessons, New Zealand organisations can transform a potentially damaging APT intrusion into a clear example of resilience, preparedness, and effective collaboration.