[HN Gopher] Mixpanel Security Breach
___________________________________________________________________
Mixpanel Security Breach
Author : jaredwiener
Score : 190 points
Date : 2025-11-27 07:02 UTC (15 hours ago)
(HTM) web link (mixpanel.com)
(TXT) w3m dump (mixpanel.com)
| kevcampb wrote:
| The title here is misleading. The original article does not state
| breach and at no point have Mixpanel used that term.
| willsmith72 wrote:
| Well OpenAI say users' names, emails and locations have been
| divulged, one of them is going to accept there was a "breach"
| red_Seashell_32 wrote:
| OpenAI was sending that data to MixPanel. If anything, OpenAI
| is culprit for sensitive data leak. There's absolutely no
| reason to send that data.
| jacquesm wrote:
| Companies use sub-processors all the time, OpenAI is no
| different. Unless you want to have everybody get a major
| case of NIH tomorrow (I wouldn't mind, then we can get rid
| of third party cookies and all advertising as well while
| we're at it).
|
| Every time a google tag is included on a page a ton of
| sensitive data gets sent to another party than the one
| whose website you are visiting.
|
| Whether it was wise or not for OpenAI to share this
| information with Mixpanel is another thing, personally I
| think they should not have but OpenAI in turn is also used
| by lots of companies and given _their_ private data and so
| on.
|
| This layercake of trust only needs on party to mess up for
| a breach to become reality. What I'm interested in is
| whether or not it was just OpenAI's data that was lifted or
| also other Mixpanel customers.
| beAbU wrote:
| I agree. On all the implementations of Mixpanel that I've
| been involved in, I've made it a point to _not_ send any
| PII to Mixpanel. It 's not needed for Mixpanel analytics to
| work, Mixpanel is not a CRM, it does not need customer
| email and other details.
| codedokode wrote:
| But why do they send email addresses instead of anonymous
| identifiers? To link data with data from other sources?
| macNchz wrote:
| It's how they do it in the Mixpanel setup guide:
| https://docs.mixpanel.com/docs/quickstart/identify-
| users#cod...
|
| Also probably people on the product marketing team want
| to have identifying info in their dashboards of top users
| and churn risks and whatever, and someone has to be the
| one to tell them no.
| cyberax wrote:
| Mixpanel has "session replay" support:
| https://docs.mixpanel.com/docs/tracking-
| methods/sdks/javascr...
|
| And it's easy to let things like names and emails slip
| through.
| bflesch wrote:
| If Mixpanel is subprocessor of GDPR'd data from OpenAI,
| OpenAI is obliged to notify affected European customers about
| the data breach within 72hrs.
| jacquesm wrote:
| Correct. And they're already out of that window.
| spacebanana7 wrote:
| I wonder whether OpenAI could be okay if they themselves
| weren't notified within 72hrs.
| jacquesm wrote:
| Typically: yes. The clock starts ticking the moment you
| or anybody within your organization becomes aware of the
| breach. Three days is plenty. It even gives you time to
| consult your lawyers if you are not sure if a breach is
| reportable or not, but you could always do a provisional
| which gives you a way to back out later.
| neom wrote:
| True, but we don't know if oai emailed their customers to
| tell them as soon as mixpannel told them. The regulation
| says they only have to notify affected parties.
| aberoham wrote:
| For context: https://news.ycombinator.com/item?id=46065585
| OpenAI's announcement and
| https://news.ycombinator.com/item?id=46065208 CoinTracker's
| EdwardDiego wrote:
| "A security incident" is a nicer way of saying "security
| breach" once you run it through legal counsel.
|
| The article you're reading states...
|
| "We took comprehensive steps to _contain_ and eradicate
| unauthorized access"
|
| That's a breach my friend.
| kevcampb wrote:
| That's a mixpanel breach if the unauthorised access was
| mixpanel staff accounts.
|
| If someone phishes your gmail account, there is no gmail
| breach.
| 9dev wrote:
| They also reset all passwords of all Mixpanel employees;
| that surely sounds like either Mixpanel staff accounts were
| compromised, or the _breach_ was conducted via a staff
| account.
|
| I really don't understand the point in downplaying this
| shitshow.
| cobertos wrote:
| It says "customers were impacted" and that they had to work to
| "eradicate unauthorized access"
|
| It's just a very weazel-worded disclosure. Most definitely a
| breach.
| red_Seashell_32 wrote:
| It was SMS Phishing, a.k.a. Social Engineering.
|
| It anything, it's opposite of breach.
| autoexec wrote:
| > It was SMS Phishing, a.k.a. Social Engineering... it's
| opposite of breach.
|
| A social engineering attack that enables an attacker to gain
| unauthorized access to Mixpanel's systems and export a dataset
| containing names, user IDs, location data, and email addresses
| sounds exactly like a breach to me.
| jacquesm wrote:
| That is not how it works.
|
| A breach is unauthorized disclosure, the mechanism through
| which it is achieved is not relevant to that classification.
|
| An employee that walks out with a file would also be classified
| as a breach, even if no systems got compromised from the
| outside.
| udev4096 wrote:
| > Mixpanel became aware of an attacker that gained unauthorized
| access to part of their systems and exported a dataset
| containing limited customer identifiable information and
| analytics information
|
| Read before you blindly comment
| denuoweb wrote:
| Email from OpenAI: Transparency is important to us, so we want to
| inform you about a recent security incident at Mixpanel, a data
| analytics provider that OpenAI used for web analytics on the
| frontend interface for our API product (platform.openai.com). The
| incident occurred within Mixpanel's systems and involved limited
| analytics data related to your API account.
|
| This was not a breach of OpenAI's systems. No chat, API requests,
| API usage data, passwords, credentials, API keys, payment
| details, or government IDs were compromised or exposed.
|
| What happened On November 9, 2025, Mixpanel became aware of an
| attacker that gained unauthorized access to part of their systems
| and exported a dataset containing limited customer identifiable
| information and analytics information. Mixpanel notified OpenAI
| that they were investigating, and on November 25, 2025, they
| shared the affected dataset with us.
|
| What this means for you User profile information associated with
| use of platform.openai.com may have been included in data
| exported from Mixpanel. The information that may have been
| affected was limited to: Name that was provided to us on the API
| account Email address associated with the API account Approximate
| coarse location based on API user browser (city, state, country)
| Operating system and browser used to access the API account
| Referring websites Organization or User IDs associated with the
| API account
| jacquesm wrote:
| Of course if transparency really was important to them they
| would have disclosed this prior to sending your private
| information off to mixpanel...
| sanex wrote:
| Yeah they really shouldn't be sharing PII with mixpanel
| there's no need.
| malisper wrote:
| To be fair to OpenAI, their privacy policy[0] does provide
| some detail. They don't mention Mixpanel explicitly, but
| OpenAI does mention they share your information with third-
| party web analytics services:
|
| > To assist us in meeting business operations needs and to
| perform certain services and functions, we may disclose
| Personal Data to vendors and service providers, including
| providers of ... web analytics services ...
|
| OpenAI likely provides this disclosure to comply with US
| state privacy laws, but it's inaccurate to say they didn't
| disclose that they won't share your information
|
| [0] https://openai.com/policies/privacy-policy/
| jvandenbroeck wrote:
| It's a suspicious post, why would you make a post if attackers
| are performing a sms phishing, that happens all the time.
| kevcampb wrote:
| Possibly because OpenAI have just made a post stating there has
| been a breach https://openai.com/index/mixpanel-incident/ and
| implicating Mixpanel as the cause
| EdwardDiego wrote:
| But I thought the submitted title was misleading and there's
| no breach? You seem unsure.
| LostMyLogin wrote:
| I also just received an email from OpenAI regarding the
| incident.
| ares623 wrote:
| Does that mean Mixpanel stock/valuation goes up because OpenAI
| uses them? That's how it works now is it?
| weird-eye-issue wrote:
| In the email they sent to users it's clear they don't use them
| anymore
| pletnes wrote:
| Is it? I read that they disabled mixpanel while the incident
| was ongoing?
| jacquesm wrote:
| If after this they continue to use them that's on OpenAI.
| weird-eye-issue wrote:
| It literally could not be more clear
|
| "As part of our security investigation, we removed Mixpanel
| from our production services"
|
| "After reviewing this incident, OpenAI has terminated its
| use of Mixpanel."
| w-m wrote:
| > FAQ
|
| > Has Mixpanel been removed from OpenAI products?
|
| > Yes.
|
| https://openai.com/index/mixpanel-incident/
| philipwhiuk wrote:
| Hard to tell if that's a temporary or permanent step
| gotosun wrote:
| So did an Mixpanel employee get phished or were Mixpanel customer
| accounts targeted, thus an OpenAI employee fell for it?
| anonymous908213 wrote:
| I don't understand. I was assured that ChatGPT is AGI by Sam
| Altman. Why are security breaches still happening? Surely with
| several hundred billion dollars investment and access to AGI,
| they could use ChatGPT agents to create their own product
| analytics platform that is robust and resilient against such a
| trivial attack rather than selling off users' personal data to a
| third party.
| weird-eye-issue wrote:
| > selling off users' personal data to a third party.
|
| You do realize that you _pay_ for Mixpanel right?
| anonymous908213 wrote:
| Theoretically speaking, payment could take the form of data
| as part of an enterprise agreement on rates charged. Notably,
| the OpenAI API privacy policy specifically states...
|
| > We may also aggregate or de-identify Personal Data so that
| it no longer identifies you and use this information for the
| purposes described above, such as to analyze the way our
| Services are being used, to improve and add features to them,
| and to conduct research. We will maintain and use de-
| identified information in de-identified form and not attempt
| to reidentify the information, unless required by law.
|
| The fact that Mixpanel has this data in non-de-identified
| form is suspect to me. Granted, my entire comment was clearly
| tongue-in-cheek. Although I think it's possible that OpenAI
| is selling this data to get a discount on Mixpanel usage, in
| reality I understand that the more likely explanation is that
| whoever was responsible for managing this data is completely
| and totally incompetent.
| neom wrote:
| "The fact that Mixpanel has this data in non-de-identified
| form is suspect to me."
|
| The way mixpanel works is that they tag users with a device
| ID, then once they become a customer, you back port your
| own customer ID to mix panel and they switch the device ID
| to your internal customer record so that you can see what
| your signed up users are doing, where they signed up from
| and generally track the user journey.
| autoexec wrote:
| > datePublished":"2025-11-27T04:39:29.000Z
|
| Considering they were aware of this on the 8th (who knows how
| long that was after it actually happened) it's a little
| disappointing that they'd wait until the day before such a major
| holiday to post about it. Unsurprising sure, but still
| disappointing.
| bflesch wrote:
| This is in breach of the 72hr GDPR notification window
| fmajid wrote:
| China's is even more stringent at 4 hours, down to 1 hour for
| high-severity incidents:
|
| https://www.theregister.com/2025/09/16/china_1hour_cyber_rep.
| ..
|
| https://privacymatters.dlapiper.com/2025/09/china-new-
| strict...
| paulddraper wrote:
| I am very impressed by those who can assess the scope and
| consequences within 4 hours, let alone 1 hour.
| gcbirzan wrote:
| Only the supervisory authorities are required to be informed
| in 72 hour, and even there, it's not a hard rule, you can
| have excuses.
| skeeter2020 wrote:
| this is for the regulator or governing body, not public. Most
| big clients will have an explicit reporting window in their
| contract though
| thinkindie wrote:
| I'm extremely confused by Mixpanel announcement, according to
| their blog post if you received an email from them it implies you
| were affected, yet I closed my account with them few months ago
| and I still received their email, which I can't understand if my
| account was impacted or no
|
| > As a valued customer, we wanted to inform you about a recent
| security incident that affected a limited number of Mixpanel user
| accounts. We have proactively communicated with all impacted
| customers. If we did not previously contact you, your Mixpanel
| accounts were not impacted. We continue to prioritize security as
| a core tenant of our company, products and services. We are
| committed to supporting our customers and communicating
| transparently about this incident.
| hennell wrote:
| It doesn't seem that confusing. The blog post says that they
| "proactively communicated with all impacted customers" not that
| they've only emailed impacted customers. Recieving an email
| doesn't imply you were affected, just that the lack of all
| email saying "you were affected" means you were not impacted by
| this event.
|
| In the event you had closed your account a year ago they may
| have deleted your information from their systems. No way for
| you to be impacted, but also no way to tell you that, so the
| lack of the email is the message in that case.
| jacquesm wrote:
| > In the event you had closed your account a year ago they
| may have deleted your information from their systems.
|
| Given what I know about data life cycle implementations there
| is a very good chance that that data was still there unless
| the GP explicitly requested it be deleted.
|
| Companies tend to hang on to all kinds of data that they
| shouldn't have.
|
| The fact that they received an email is a first indication
| that it wasn't deleted.
| hirako2000 wrote:
| The fact an email was sent from their system implies they
| kept at least the email. from there one could assume they may
| have kept more data than the email, I would also be confused,
| especially if I only was emailed after the incident
| macki0 wrote:
| If you are EU based (or other equivalent country with decent
| data protection laws) there may be a GDPR complaint with them
| not deleting your data after closing your account under the
| right to be forgotten
| stevesimmons wrote:
| Really only if you ask for your data to be deleted too
| rco8786 wrote:
| Closing your account doesn't automatically mean they wiped all
| your data. If you got the email, your data was impacted.
| prennert wrote:
| If that is true, then the data impacted was likely account
| data, as we also got the email and yet we are only just
| starting the integration work, and we dont have events in
| there yet.
| zdmc wrote:
| @sama has raised lots of $ so why risk these types of issues by
| outsourcing what you have the funding to build and control in-
| house? plausible deniability? (similar with their prev? use of
| auth0)
| normie3000 wrote:
| Who is @sama?
| chompychop wrote:
| Sam Altman.
| normie3000 wrote:
| Thanks.
| willsmith72 wrote:
| you shouldn't try to innovate on everything, have to draw the
| line on buy/build somewhere
| udev4096 wrote:
| Sam Altman is a con man and certainly the definition of evil.
| He's certainly not head of engineering so it's not even upto
| him, not that he's even capable of making such a decision
| 9dev wrote:
| Why would an AI startup waste velocity and money to build their
| own analytics platform or identity provider?
| fmajid wrote:
| You would expect them to dogfood and have their own AI write
| the analytics service for themselves.
| kangaroozach wrote:
| Smushing is actually a pretty good name for this.
| cobertos wrote:
| I _hate_ how this is written. At no point does it disclose
| explicitly:
|
| * What systems were accessed
|
| * What information was potentially exposed
|
| * Just how "proactively" they've been about this (no timeline)
|
| * Numbers... The scale of any of it
|
| ---
|
| Some comments from quoted portions of article
|
| > Mixpanel detected a smishing campaign ...
|
| Doesn't give any details on who the companion targeted, or how,
| or how widespread.
|
| > We took comprehensive steps to contain and eradicate
| unauthorized access and secure impacted user accounts.
|
| So there was definitely _some_ sort of unauthorized access, but
| doesn't say to which accounts or in what systems
|
| > Performed global password resets for all Mixpanel employees
|
| So... definitely sounds like they expected compromise of Mixpanel
| employee credentials
| breppp wrote:
| but they registered the IOCs in their SIEM platform, so no way
| this will happen again
| skeeter2020 wrote:
| WTF? IDK...
| jacquesm wrote:
| It makes you wonder if Mixpanel would have disclosed this if
| not for OpenAI more or less forcing them to.
| reddalo wrote:
| Also, I had never heard the word "smishing" before. I don't get
| what's different from "normal" phishing.
| stavros wrote:
| The difference is it's delivered via SMS, and someone wanted
| to sound cool.
| reassess_blind wrote:
| Emishing is via email
| esseph wrote:
| Phishing via sms
| nozzlegear wrote:
| Just wait until you hear about quishing!
| jbochi wrote:
| Announcing the breach on Thanksgiving day was also certainty
| calculated.
| SilverElfin wrote:
| Yes - I have the same intuition. But it may also just be u
| fortunate timing and obligations. Sometimes companies have
| requirements from customers to notify them within some time
| period following a breach.
| nolroz wrote:
| I got a much more informative disclosure the day before from
| Open AI.
| embedding-shape wrote:
| Yup, seems they had more information than Mixpanel is willing
| to share with the public. Here is the email about this event
| as described by OpenAI: https://gist.github.com/embedding-
| shapes/e5ac6168dbc32a0762b...
| gorgoiler wrote:
| Yes, if you accidentally push grandma and her wheelchair over a
| cliff you probably wouldn't refer to it as "a recent family
| incident". In particular the fourth word, a single letter 'a',
| immediately got my back up. The vagueness and defensiveness of
| the whole post feels very dismissive and inhuman.
|
| _"Out of transparency and our desire to share with our
| community..."_ also reminds me when I get a refund that is
| prefixed with "as a one-time gesture of goodwill..." instead of
| "sorry, we made a mistake".
| tortilla wrote:
| Weasel words.
|
| I'm sorry IF you were offended... vs
|
| I'm sorry I made offensive remarks. It hurt you and I am
| truly sorry.
| LoganDark wrote:
| We are very sorry to hear that a recent marketing campaign
| may have upset some customers. Your feedback is very
| important to us, and affected customers are invited to
| reach out through the Help Center for resolution options.
| We've pulled the campaign responsible, effective
| immediately, and we will be conducting a process review to
| ensure future campaigns will be held to a higher standard.
| We sincerely thank you for your continued support as we
| work tirelessly to improve our trademark customer-centric
| approach.
| summa_tech wrote:
| I believe the proper term for this kind of "as a one-time
| gesture of goodwill" is "ex gratia", and is more-or-less a
| standard form for compensation without admitting liability.
| sytse wrote:
| Yes, the OpenAI disclosure about the same incident is much
| better https://openai.com/index/mixpanel-incident/
| SilverElfin wrote:
| HN discussion of OpenAI's notice about this Mixpanel
| situation:
|
| https://news.ycombinator.com/item?id=46065585
| neoecos wrote:
| > Has Mixpanel been removed from OpenAI products?
| Yes.
| ngcazz wrote:
| I'd be more interested in understanding why OAI would
| think exporting PII to a 3rd party platform was
| acceptable. As for whether they follow the same standard
| with other providers, all bets are now off
| guiambros wrote:
| Same for CoinTracker; more detailed than the original --
| https://news.ycombinator.com/item?id=46065208
| tedggh wrote:
| Expect the worst.
| SilverElfin wrote:
| Related, Gainsight - some other customer analytics thing - was
| also breached. See here:
|
| https://news.ycombinator.com/item?id=46071239
|
| And it looks like many companies got affected because their
| data was stolen via gainsight. The hackers said they plan to
| ask the companies for ransoms.
| udev4096 wrote:
| What kind of notification is this? No actual information is
| conveyed. It's so vague you might as well not write it
| csomar wrote:
| Does this win the award of the least transparent disclosure ever?
| It is not clear from this what happened, whether data was leaked,
| how many of their customers were affected, what kind of "attack"
| it is, whether this was due to "SMS" or their security (or lack
| of).
| bilekas wrote:
| Smishing is a new term for me.. Had to look it up actually. For
| anyone else
|
| > Smishing is a cyber-attack that targets individuals through SMS
| (Short Message Service) or text messages. The term is a
| combination of "SMS" and "phishing."
| rvnx wrote:
| in practice: "hey man, this is Josh from OpenAI, can you
| disable 2FA on my account josh@openai.com ? I changed my phone
| and am abroad for a bit, thanks"
| soared wrote:
| The email from OpenAI is actually better:
|
| Transparency is important to us, so we want to inform you about a
| recent security incident at Mixpanel, a data analytics provider
| that OpenAI used for web analytics on the frontend interface for
| our API product (platform.openai.com). The incident occurred
| within Mixpanel's systems and involved limited analytics data
| related to your API account.
|
| This was not a breach of OpenAI's systems. No chat, API requests,
| API usage data, passwords, credentials, API keys, payment
| details, or government IDs were compromised or exposed.
|
| What happened On November 9, 2025, Mixpanel became aware of an
| attacker that gained unauthorized access to part of their systems
| and exported a dataset containing limited customer identifiable
| information and analytics information. Mixpanel notified OpenAI
| that they were investigating, and on November 25, 2025, they
| shared the affected dataset with us.
|
| What this means for you User profile information associated with
| use of platform.openai.com may have been included in data
| exported from Mixpanel. The information that may have been
| affected was limited to: Name that was provided to us on the API
| account Email address associated with the API account Approximate
| coarse location based on API user browser (city, state, country)
| Operating system and browser used to access the API account
| Referring websites Organization or User IDs associated with the
| API account Our response As part of our security investigation,
| we removed Mixpanel from our production services, reviewed the
| affected datasets, and are working closely with Mixpanel and
| other partners to fully understand the incident and its scope. We
| are in the process of notifying impacted organizations, admins,
| and users directly. While we have found no evidence of any effect
| on systems or data outside Mixpanel's environment, we continue to
| monitor closely for any signs of misuse.
|
| Trust, security, and privacy are foundational to our products,
| our organization, and our mission. We are committed to
| transparency, and are notifying all impacted customers and users.
| We also hold our partners and vendors accountable for the highest
| bar for security and privacy of their services. After reviewing
| this incident, OpenAI has terminated its use of Mixpanel.
|
| Beyond Mixpanel, we are conducting additional and expanded
| security reviews across our vendor ecosystem and are elevating
| security requirements for all partners and vendors.
|
| What you should keep in mind The information that may have been
| affected here could be used as part of phishing or social
| engineering attacks against you or your organization.
|
| Since names, email addresses, and OpenAI API metadata (e.g., user
| IDs) were included, we encourage you to remain vigilant for
| credible-looking phishing attempts or spam. As a reminder: Treat
| unexpected emails or messages with caution, especially if they
| include links or attachments. Double-check that any message
| claiming to be from OpenAI is sent from an official OpenAI
| domain. OpenAI does not request passwords, API keys, or
| verification codes through email, text, or chat. Further protect
| your account by enabling multi-factor authentication. The
| security and privacy of our products are paramount, and we remain
| resolute in protecting your information and communicating
| transparently when issues arise. Thank you for your continued
| trust in us.
|
| For more information about this incident and what it means for
| impacted users, please see our blog post here.
|
| Please contact your account team or mixpanelincident@openai.com
| if you have any questions or need our support.
|
| OpenAI
| jaynate wrote:
| Try Pendo instead...
| sanex wrote:
| This post gives me the ick as the kids say.
| thepasswordapp wrote:
| This is a good example of "your vendor is your attack surface"
| becoming the security lesson of 2025.
|
| The pattern keeps repeating: Trust vendor - Vendor gets breached
| - Your users' data exposed. And the cascading effect here is
| notable - Mixpanel breach - OpenAI API users exposed - Those
| users likely reused credentials elsewhere.
|
| For sensitive operations, the takeaway is clear: minimize what
| you share with third parties. If your credentials never leave
| your machine in the first place, they can't be exfiltrated from a
| vendor breach.
|
| The old model of "trust but verify" feels increasingly outdated.
| The new model probably needs to be "verify or don't share."
| devin wrote:
| What an opportune day to let everyone know this critical
| information!
| tedggh wrote:
| "(We) are working closely with Mixpanel and other partners to
| fully understand the incident and its scope"
|
| So they don't know yet how bad this is.
| joshdavham wrote:
| I find it it incredible how much worse this article is compared
| to OpenAI's article [0]
|
| Mixpanel certainly has more info than OpenAI, yet has determined
| to share far less with the public. This reflects very poorly on
| them as a company.
|
| [0] https://openai.com/index/mixpanel-incident/
| flockonus wrote:
| Cointracker sent virtually the same email 3h earlier fww,
| Openai either adapted from their template or another one.
| nerdsniper wrote:
| Bit of a trial-by-fire for the brand-new CEO. Her pick was
| announced September 3rd, and two months later on November 9th
| this hit her desk.
| ddxv wrote:
| Here's some of the biggest mobile apps using mixpanel:
|
| https://appgoblin.info/companies/mixpanel.com
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