Remember the Ashley Madison data breach? That was now more than a decade ago, yet it arguably remains the single most noteworthy data breach of all time. There are many reasons for this accolade, but chief among them is that by virtue of the site being expressly designed to facilitate extramarital affairs, there was massive social stigma attached to it. As a result, we saw some pretty crazy stuff:

1. Various websites were stood up to publicly disclose the presence of people in the data and out them as “cheaters”
2. Churches trawled through the data and contacted the spouses of exposed parishioners
3. The media outed noteworthy individuals they searched for in the breach
4. A radio station back home in Australia encouraged listeners to dial in to check if their spouse was in the data

Arguably, we now live in a more privacy-conscious era, one full of acronyms such as GDPR and CCPA, among others, in different parts of the world. The right to be forgotten, the right to erasure, and, indeed, privacy as a fundamental human right feature very differently in 2026 than they did in 2015. But arguably, even back then, the impact of outing someone as a member of the site should have been obvious. It was certainly obvious to me, which is why I introduced the concept of a sensitive data breach before the data even went public. HIBP wouldn’t show results for this breach publicly because I was concerned about the impact on people being outed. My worst fear was a spouse coming home to find someone having taken their own life, an HIBP search result on the screen in front of their lifeless body.

People died as a result of the breach. Marriages ended and lives were turned upside down. People lost their jobs. The human toll of the breach was profound. The decision I made after witnessing this was that if a breach was likely to have serious personal or social consequences for people in there, it would be flagged as sensitive and not publicly searchable.

The public doxing of members of the service was often justified on a moral basis: “adultery is bad, they deserve to be outed”. But there are two massive problems with this attitude, and I’ll begin with the purpose for which accounts were sometimes made:

An email address appearing in that breach implied that the person was there to have an extramarital affair because that was literally the catch-phrase of the service: “Life is short, have an affair”. But the reality was that people were members of the service for many, many different reasons. Have a read of my post titled Here’s What Ashley Madison Members Have Told Me and you’ll begin to understand how much more nuanced the situation was:

1. Single people had joined the service, and later married before the breach occurred
2. People who were worried about a cheating spouse joined the service in order to try to catch them
3. Accounts were made with some people’s names and email addresses without their consent (there are many “Barrack Obamas” in the data)

So, should everyone with an email address on Ashley Madison be considered an adulterer? Clearly, no, that completely misses the nuances of what an email address in a data breach really means. But what about the people who were there to have an affair? Well, that brings us to the second problem:

Our own personal belief systems are not a valid basis for outing people publicly because their belief systems differ. I used more generic terms than “extramarital affair” or “cheating” because there are many other data breaches that are flagged as sensitive in HIBP for the very same reason. Fur Affinity, for example: there is a social stigma around furries and outing someone as a member of that community could have negative consequences for them. Rosebutt Board is another example: anal fisting is evidently something a bunch of people are into, and equally, I’m sure there are many who take a moral objection to it. And finally, to get to the catalyst for this post, WhiteDate: the website that is ostensibly designed for white people to date other white people. Flagging that as sensitive resulted in some unsavoury commentary being directed at me:

U are a Nazi end of story

— 𝔗𝔥𝔢ℑ𝔡𝔦𝔬𝔱 (@fuckelonsob) January 6, 2026

Now, I emphasised “ostensibly” because the more you dig into this breach, the more you find tones of white supremacy and other behaviours that definitely don’t align with my personal value system. That societal view doesn’t sit well with me, and I think I’m safe in saying it wouldn’t sit well with most people. Would someone being outed as a member of that service be likely to result in “serious personal or social consequences”? Yes, and you can see that in the messaging from the same account:

Context matters. U are literally shielding Nazi hate mongering scoundrels. We can't doxx white supremacists?

If ISIS had a dating site & it got breached, would you protect it out of fear of doxxing? No.

Every database leaked is sensitive in a way.

— 𝔗𝔥𝔢ℑ𝔡𝔦𝔬𝔱 (@fuckelonsob) January 6, 2026

This behaviour is precisely what I don’t want HIBP being used for: as a weapon to attack people solely on the basis of their email address being affiliated with a website that has had a data breach.

Imagine, for a moment, if ISIS did have a dating site and it was breached, should it be flagged as sensitive? Contrary to the comment about "every database leaked is sensitive", there is a clear legal definition for sensitive personal information and it includes:

personal data revealing racial or ethnic origin, political opinions, religious or philosophical beliefs;

trade-union membership;

genetic data, biometric data processed solely to identify a human being;

health-related data;

data concerning a person’s sex life or sexual orientation.

An ISIS dating website breach would tick many of the boxes above and would therefore constitute a sensitive data breach. That's not an endorsement of what they stand for; it's simply a data-processing decision. But there may be a nuance in there which I didn't see present in the WhiteDate data - what if it contained illegal activity? (Sidenote: for the most part, HIBP is used by people in Western Europe, North America and Australasia, so when I say "illegal", I'm looking at it through that lens. Clearly, there are parts of the world where our "illegal" is their "normal", which further complicates how I run a service accessible from every corner of the world.) I had another example recently that went well beyond moral contention and deep into the realm of illegality:

New sensitive breach: "AI girlfriend" site Muah[.]ai had 1.9M email addresses breached last month. Data included AI prompts describing desired images, many sexual in nature and many describing child exploitation. 24% were already in @haveibeenpwned. More: https://t.co/NTXeQZFr2x

— Have I Been Pwned (@haveibeenpwned) October 8, 2024

Of all the different things people can disagree on when it comes to our moral compasses, paedophilia is where we unanimously draw the line. But I still flagged it as sensitive because of the reasons outlined above. Many people using the service were just lonely guys trying to create an AI girlfriend with no prompts around age. There would be email addresses in there that weren’t entered by the rightful owner. And then, there are cases like this:

That's a firstname.lastname Gmail address. Drop it into Outlook and it automatically matches the owner. It has his name, his job title, the company he works for and his professional photo, all matched to that AI prompt. pic.twitter.com/wpXQMBLf3B

— Troy Hunt (@troyhunt) October 9, 2024

I sat there with my wife, looking at the LinkedIn profile that used the same email address as the person who posted that comment. We looked at his photo and at the veneer of professionalism that surrounded him on that site, knowing what he had written in that prompt above. It was repulsive. Further, beyond being solely an affront to our morals, it was clearly illegal. So, I had many conversations with law enforcement agencies around the world and ensured they had access to the data. Involving law enforcement where data sets contain illegal activity is absolutely the right approach here, but equally, not being the vehicle for implying someone’s affiliation or beliefs and doxing them publicly without due process is also absolutely the right approach.

I understand the gut reaction that flagging a breach like WhiteDate as sensitive protects people whom most of us do not like. But a dozen years of running this service have caused me to consider individual privacy and rights literally hundreds of times, and these conclusions aren’t arrived at hastily. Imagine for a moment, the possible ramifications for HIBP if the service were used to publicly shame someone as a "Nazi" and that, in turn, had serious real-world consequences for them. Whether that implication was right or not, there are potentially serious ramifications for us that could well leave us unable to operate at all. And, as the Ashley Madison examples show, there are also potentially life-threatening outcomes for individuals.

I don't particularly care about one random, anonymous X account making poorly thought-out statements, but the same sentiment has been expressed after loading previous similar breaches, and it deserves a blog post. Equally, I've written before about why all the other data breaches are publicly searchable and again, that conclusion is not arrived at lightly.

I’ll finish with a note about privacy that relates to my earlier comment about it being a human right. It's literally a human right under Article 12 of the Universal Declaration of Human Rights:

No one shall be subjected to arbitrary interference with his privacy, family, home or correspondence, nor to attacks upon his honour and reputation. Everyone has the right to the protection of the law against such interference or attacks.

Breaches with legally defined sensitive data will continue to be flagged as sensitive, and breaches with illegal data will continue to be forwarded to law enforcement agencies.