Nigeria’s National Information Technology Development Agency (NITDA) has issued an urgent cybersecurity advisory highlighting newly discovered vulnerabilities in OpenAI’s GPT-4.0 and GPT-5 series, as well as security risks affecting Cisco firewall devices used across enterprises.
The agency, through its Computer Emergency Readiness and Response Team (CERRT.NG), identified seven critical weaknesses in the GPT models that could allow attackers to manipulate ChatGPT via indirect prompt injections embedded in seemingly harmless webpages, comments, or URLs. These hidden instructions could cause ChatGPT to execute unintended commands during browsing, summarisation, or search activities.
Some vulnerabilities are particularly concerning as they could bypass safety filters using trusted domains, exploit markdown rendering flaws, or even “poison” ChatGPT’s memory, causing malicious instructions to persist across future interactions. NITDA warns that this could lead to unauthorized actions, data leakage, manipulated outputs, and long-term behavioral influence, potentially affecting both individuals and enterprise systems.
While OpenAI has implemented partial fixes, NITDA cautions that large language models still face inherent challenges in distinguishing legitimate user input from malicious content. To mitigate risks, the agency recommends:
- Limiting or disabling browsing and summarisation features for untrusted sites.
- Enabling memory or browsing features only when necessary.
- Regularly updating GPT-4.0 and GPT-5 models to ensure known vulnerabilities are patched.
In a related advisory, NITDA also warned of a fresh attack method targeting Cisco Secure Firewall ASA and Cisco Secure Firewall Threat Defense (FTD) systems. Cybercriminals are exploiting older vulnerabilities to trigger unexpected device reboots, which can cause network instability, service disruption, and denial-of-service for businesses, banks, government offices, and internet service providers.
Mrs. Hadiza Umar, NITDA’s Director of Corporate Affairs and External Relations, emphasized the need for organisations to act quickly, apply patches, and adopt best practices to safeguard against these emerging threats.
The advisory underscores growing cybersecurity challenges in Nigeria and the need for vigilance, regular updates, and proactive risk management across digital platforms and enterprise networks.