OpenAI says a May 2026 compromise of TanStack npm packages affected two employee devices, prompting certificate rotation and update guidance for some macOS desktop app users.
OpenAI said it rotated macOS product-signing certificates after a TanStack npm supply chain attack affected two employee devices.
In a post titled “Our response to the TanStack npm supply chain attack,” OpenAI said TanStack npm packages were compromised on May 11, 2026. OpenAI said two employee devices were impacted as part of the incident.
OpenAI’s response included rotating code-signing certificates used for its products. On macOS, signing certificates are part of Apple’s application trust model, so certificate changes can affect whether older builds continue to launch without warnings.
OpenAI’s Help Center separately says the company’s Apple Developer signing identity changed as part of the incident response. The support article also provides current certificate fingerprints for organizations that manage macOS application allowlists.
OpenAI says some users on older desktop app builds may see macOS warnings tied to a previously revoked signing certificate. The company says users who updated Codex within the past six weeks should already have a current build.
For users still seeing warnings, OpenAI recommends updating through the app or reinstalling the latest version from OpenAI’s official download page. Forbes reported that some Mac users saw ChatGPT malware warnings and said redownloading the ChatGPT app from OpenAI applies the newer certificate and resolves the block.
The warning does not, by itself, mean that every affected user’s Mac was compromised. Based on OpenAI’s disclosure and Help Center guidance, the user-facing issue is linked to certificate rotation after the TanStack-related incident response, rather than a finding that all installed OpenAI desktop apps were malicious.
TechCrunch reported that OpenAI said hackers stole some data after the code security issue. TechCrunch also corroborated that the TanStack-related compromise led OpenAI to rotate product-signing certificates and require macOS app updates.
Forbes linked the Mac warnings seen by some ChatGPT users to OpenAI’s certificate changes and reported that reinstalling from OpenAI’s official site was the remedy for affected users.
Together, OpenAI’s incident post, its Help Center documentation, Forbes, and TechCrunch point to the same practical guidance: affected macOS users should update or reinstall OpenAI desktop software from official OpenAI sources.
OpenAI’s guidance is to update affected apps through the application itself or reinstall the latest version from OpenAI’s official download page.
For managed macOS environments, OpenAI’s Help Center article provides the current Apple Developer signing identity and certificate fingerprints. IT administrators should compare existing allowlist rules with OpenAI’s latest published fingerprints rather than relying on older signing details.
Users should avoid replacement installers from unofficial mirrors or third-party links. The cited sources identify OpenAI’s own update and download channels as the recommended way to obtain builds signed with the current certificate.
The incident shows how a compromise in a widely used open-source package ecosystem can have effects beyond the original project. OpenAI attributes the response to the TanStack npm supply chain attack, while the visible impact for some Mac users came through certificate revocation and renewed signing.
OpenAI has not said in the cited materials that general customer accounts were compromised through the macOS warning itself. The company’s public guidance focuses on certificate rotation, current app builds, and allowlisting information for organizations that verify macOS application signatures.
Hero image prompt: Editorial-style illustration of a laptop on a desk with abstract certificate seals, package blocks, and security shields connected by thin lines, conveying software supply chain security and macOS app signing; no logos, no real user interface, no readable text.
Hero image alt text: Abstract illustration of a laptop, software package blocks, certificate seals, and security shields representing code signing after a supply chain incident.
OpenAI said it rotated macOS product signing certificates after a TanStack npm supply chain attack affected two employee devices.
What OpenAI disclosed In a post titled “Our response to the TanStack npm supply chain attack,” OpenAI said TanStack npm packages were compromised on May 11, 2026.
OpenAI said two employee devices were impacted as part of the incident.
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