Communication
Telling people about an AI data breach
People must be told promptly when the breach puts them at high risk, and the message has to be written in plain language.
Last reviewed against legislation.gov.uk, National Cyber Security Centre and OWASP GenAI Security Project. Sources
The test
High risk, not any risk
Informing the regulator and informing individuals are separate decisions. The bar for individuals is higher: the breach must be one that puts their rights and freedoms at high risk [2]. Decide the two questions separately and record both answers.
The message
What goes in
The message has to describe the nature of the breach in plain language, and give at least a contact point, the consequences you expect and the measures taken or proposed [2]. In practice that means answering four questions.
What happened
Say what was exposed and how, without jargon. After its March 2023 incident, OpenAI named an open-source library bug as the cause and listed the kinds of data involved [9].
What was involved
Be exact about categories. OpenAI said complete card numbers were never exposed, and set out which details were [9]. Saying what was not exposed helps as much as saying what was.
What it means for them
Describe the likely consequences and what the person can do about them, such as changing a password or watching for suspicious messages.
Exceptions
When you need not
Individuals need not be told in three situations [2]:
- the data was protected in a way that makes it unreadable to others, such as encryption
- later steps mean the high risk is no longer likely to materialise
- telling each person would take disproportionate effort, in which case a public notice or similar measure must reach them just as effectively
Next, read reporting to the regulator.
The regulator can disagree
Where you have not told individuals, the regulator may require you to, after weighing the likelihood of high risk [2]. Record why you relied on an exception.
Keep reading
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