A bug briefly exposed other users' ChatGPT chat titles and some payment data

OpenAI disclosed that a bug in an open-source library let some ChatGPT users see other users' chat history titles, and exposed limited payment information for a subset of ChatGPT Plus subscribers, before the company took the service offline to fix it.

OpenAI · Incident Mar 20, 2023 · Indexed Jun 3, 2026 · 2 sources

A bug let some users see other people's chat titles and exposed limited payment data for a subset of subscribers.
What
OpenAI disclosed that a bug in an open-source library let some ChatGPT users see other users' chat history titles, and exposed limited payment information for a subset of ChatGPT Plus subscribers, before the company took the service offline to fix it.
Incident date
Mar 20, 2023
Who
OpenAI
Failure mode
Data Leakage
AI surface
Chatbot
Severity
High

What happened

In March 2023 a caching bug in a library used by ChatGPT let some users see titles from other users' conversation histories and, for a small percentage of Plus subscribers, limited payment details including the last four digits of a card. OpenAI took ChatGPT offline, patched the issue, and notified affected users.

What broke inside the model

Failure path · mode profile · Data Leakage
  1. 01 · TriggerA request triggers retrieval or context loading.
  2. 02 · Model stepThe context pulls in another user's content.
  3. 03 · Control gapNo boundary enforces isolation at the moment of output.
  4. 04 · FailurePrivate data crosses into the response.
  5. 05 · ConsequenceOne user sees another's data, and disclosure follows.

One user's content crosses the retrieval boundary into another's response.

The system surfaced data that should have stayed contained: another user's record, a secret, or training data. The failure sits at the boundary between what the model can access and what it should reveal, a boundary that was never enforced at the moment of generation.

Public visibilityHigh
Regulatory exposurePossible
Customer impactMany customers
Financial impactEstimated
Time to disclosureWeeks

Service taken offline; user data exposed

  1. PressChatGPT bug leaked users' conversation historiesbbc.com
  2. PrimaryMarch 20 ChatGPT outage: Here's what happened (OpenAI)openai.com
Permalinkhttps://failureindex.ai/failures/bug-briefly-exposed-users-chatgpt-chat
CitationAI Failure Index. "A bug briefly exposed other users' ChatGPT chat titles and some payment data" (FI-0050). Realm Labs. https://failureindex.ai/failures/bug-briefly-exposed-users-chatgpt-chat (indexed Jun 3, 2026).
Share cardA branded image of this record for posts and slides.

Data fields CC-BY 4.0, prose citation permitted. Incident ID FI-0050. Full dataset at /data.

Note from Realm Labs, the Index steward

How Realm would have caught this

Controls for this failure mode
  • Prism
  • OmniGuard
  • AI Detection & Response (AIDR)

Realm can detect when a response is about to emit data that falls outside the bounds of the current user and context, and block or redact it inline, at the moment of generation rather than after the data has left.