On May 8, 2026, OpenAI fully revokes the macOS code-signing certificate it used to sign ChatGPT, Codex, Codex CLI, and Atlas before April 2026. From that day on, macOS Gatekeeper refuses to launch any version still signed with the old certificate, so a perfectly familiar app icon suddenly throws a security warning instead of opening. The trigger was a March 31, 2026 supply chain attack on the popular axios npm library, which slipped into OpenAI’s GitHub Actions Mac signing pipeline and forced a full certificate rotation.
If you use the ChatGPT desktop client for Mac, this guide walks you through the 30-second update, what the warning looks like if you miss the deadline, which OpenAI apps are affected (and which are not), what OpenAI says about your data, and the multi-model option some Mac users are picking up so they stop being on the hook for any single vendor’s outage. We also flag the simple version check most write-ups skip.
The Key Takeaways
- Hard deadline: May 8, 2026. OpenAI revokes its old macOS code-signing certificate; older builds of ChatGPT, Codex, Codex CLI, and Atlas stop launching after that date.
- Safe versions are any builds released after April 20, 2026. A 30-second update from inside the app fixes it.
- Only macOS is affected. Windows, iOS, Android, and the chatgpt.com web app are unaffected.
- No user data was accessed. OpenAI says no evidence its systems, user data, or software were altered, only the build pipeline was compromised.
- Already broken? A clean reinstall from chatgpt.com/download with the new certificate fixes it. Multi-model alternatives like the Fello AI app for Mac are a backup if you want to stop relying on a single desktop client.
What’s Happening on May 8, 2026
OpenAI is revoking the Apple-issued certificate it uses to sign all four of its Mac apps. Apple builds Gatekeeper, the gatekeeping system that lives at the heart of macOS, to refuse launching any app whose signature is no longer trusted. Once the certificate is revoked, every old build looks identical to a forged or tampered binary in the eyes of macOS, even though nothing on your Mac has changed.
The reason is a textbook supply chain attack. On March 31, 2026, attackers compromised the maintainer account of axios, an HTTP client library with roughly 100 million weekly downloads across the JavaScript ecosystem. Google’s Threat Intelligence Group attributes the operation to UNC1069, a North Korea-linked group. The attackers pushed a malicious version, 1.14.1, that briefly slipped into OpenAI’s GitHub Actions workflow used to sign Mac apps. OpenAI rotated the certificate out of caution, even though forensic analysis suggested the cert was likely never exfiltrated.
The clean fix is the new certificate. OpenAI re-signed every Mac app and started shipping new builds in mid-April 2026. As long as you are running a version released after April 20, 2026, you are signed with the new certificate and nothing breaks on May 8.
How to Update Your ChatGPT Mac App in Under Two Minutes
The fastest way to update is from inside the app itself. Launch ChatGPT, click ChatGPT in the macOS menu bar at the top-left of your screen, and pick Check for Updates. If a new version is available, install it and let the app restart. If you see a banner inside ChatGPT prompting you to update, that does the same thing.
A manual download works as a fallback if the in-app updater fails or the app already refuses to open.
- Quit the ChatGPT app on Mac.
- Open Safari (or any browser) and go to chatgpt.com/download.
- Download the latest ChatGPT for macOS installer.
- Drag ChatGPT.app into your Applications folder, replacing the old version when prompted.
- Launch it from Applications. The first launch may take a few extra seconds while macOS verifies the new signature.
If you want to confirm you are on a safe build, click ChatGPT → About ChatGPT in the menu bar. The version date should be on or after April 20, 2026. Anything earlier is signed with the revoked certificate.
The macOS desktop app requires macOS 14 or newer and Apple Silicon (M1 or better). Intel Macs and older macOS releases are not supported by the official OpenAI client, which is a separate question from this certificate issue.
Today vs. After May 8: What You’ll See and What to Do
The user experience is very different depending on which side of the deadline you are on. The table below covers the four most likely scenarios.
| Status | What you’ll see | What to do | Time required |
|---|---|---|---|
| Today, app working as normal | App opens; in-app banner may suggest update | Click ChatGPT → Check for Updates; install | ~30 seconds |
| Today, in-app update prompt visible | Yellow or blue banner inside ChatGPT | Accept the prompt; restart when it asks | ~1 minute |
| After May 8, app refuses to open | Gatekeeper alert: “ChatGPT is damaged and can’t be opened” or “cannot be verified” | Download fresh installer from chatgpt.com/download; replace old app | ~3 minutes |
| After May 8, app opens but updater stuck | App launches but won’t fetch updates | Quit, delete from Applications, reinstall from chatgpt.com/download | ~3 minutes |
The Gatekeeper warning is alarming the first time you see it. It uses the same wording macOS uses for actually malicious binaries, which is exactly why OpenAI is rotating the certificate. Any app signed with that cert has to come down with it.
All Four OpenAI Mac Apps Are Affected
The certificate change is not just a ChatGPT problem. The same OpenAI signing pipeline issued the certificates for every Mac app the company ships. If you have any of the following installed, each one needs the same update.
ChatGPT Desktop is the consumer-facing client most people on FelloAI use. It is the highest-volume app affected and the one you are most likely to see in your Applications folder.
Codex is OpenAI’s coding-focused desktop client. If you write code with it on Mac, it needs the same update path as ChatGPT.
Codex CLI is the terminal tool many developers wire into shell scripts. The May 8 revocation hits CLI binaries the same way it hits the GUI apps; reinstall via brew or whatever package manager you used originally.
Atlas is the OpenAI browsing client. Less common on Mac than the other three, but if it is installed it follows the same fix.
You should not assume that because ChatGPT updated cleanly, the others did. Each app maintains its own update channel, so confirm each one separately.
What If Your App Already Stopped Working?
If you are reading this past May 8 and ChatGPT will not launch, the in-app updater is probably no longer reachable. The clean recovery path is a fresh install. Quit any running ChatGPT processes from Activity Monitor, drag the existing ChatGPT.app out of Applications to the Trash, and download the latest installer from chatgpt.com/download. The new build is signed with the rotated certificate and Gatekeeper will accept it on launch.
You will not lose your conversation history. ChatGPT history lives on OpenAI’s servers tied to your account, not in the app bundle. After reinstalling, sign back in and your chats are exactly where you left them.
If macOS still flags the new binary as damaged after a clean reinstall, your Keychain is probably caching the revoked certificate. Open Keychain Access, search for “OpenAI” or “ChatGPT”, delete any expired or revoked entries, and try the install again. This is rare but happens on machines that were running multiple old builds.
Was My ChatGPT Data Compromised?
OpenAI’s official advisory on the Axios incident is direct on this point. The company writes that it “found no evidence that OpenAI user data was accessed, that our systems or intellectual property was compromised, or that our software was altered.” The compromise hit the build pipeline, not the production servers, and the certificate rotation is a precautionary control to make sure nobody can sign a fake “OpenAI” Mac app using the leaked credentials in the future.
Independent reporting from The Hacker News and BleepingComputer corroborates that read; both note OpenAI engaged a third-party digital forensics firm and that no production systems showed signs of compromise. You can read OpenAI’s own writeup of the event on its Axios developer tool compromise advisory.
That is good news for your account, your billing, and your stored conversations. The bad news is that supply chain attacks on developer tooling are becoming common enough that this won’t be the last one, which is the broader point worth thinking about.
Why This Keeps Happening, and a Multi-Model Alternative
Single-vendor desktop clients are fragile by design. When one company controls the signing certificate, the auto-updater, and the model behind your chat, any one of those breaking takes the whole product down with it. ChatGPT has gone through outages, login issues, model deprecations, and now a certificate revocation in the past 12 months alone. Most Mac users patch each one and move on. That works fine until you hit a workday where the app will not launch, and the work piling up on your desk does not care why.
If you want a backup, Fello AI app for Mac is a Mac and iOS client that bundles ChatGPT, Claude, Gemini, Grok, and DeepSeek under one $9.99/month subscription. The point is not to replace ChatGPT. The point is that one vendor’s signing issue stops being your problem when you can switch models inside the same app and keep working. It is the same logic many teams use for cloud providers; redundancy beats reliability claims. If you want background on how that comparison shakes out, our best AI models in 2026 roundup covers the trade-offs in detail.
For Mac users specifically, our guide to the best ChatGPT alternatives for Mac rates the multi-model clients side by side, including how each one handles outages, model switching, and pricing.
Conclusion
The May 8 deadline is a 30-second fix if you act today and a slightly more annoying reinstall if you wait. Either way it is recoverable, your data is fine, and your account is fine. The longer-term takeaway is the one most security-news sites skipped. Single-vendor desktop clients fail in single-vendor ways, and a single bad cert rotation can take an entire workflow down with it. If your workflow can survive a one-day ChatGPT outage, do nothing past clicking Check for Updates. If it can’t, line up a multi-model fallback before the next one of these inevitably lands.
If you want to compare the native Mac clients head to head, our Claude AI desktop client for Mac and Gemini desktop app for Mac pages cover the two strongest alternatives in detail.
FAQ
What time on May 8 does the ChatGPT Mac app stop working?
OpenAI has not published a specific time of day. Treat it as in effect from the start of May 8 in your local timezone. Updating before May 7 is the safest option.
What version of ChatGPT for Mac is safe?
Any build released after April 20, 2026. You can confirm by clicking ChatGPT → About ChatGPT in the macOS menu bar. Builds dated earlier are signed with the revoked certificate and stop launching on May 8.
Are Windows, iOS, or web ChatGPT users affected?
No. The certificate revocation is specific to macOS code signing. Windows, iOS, Android, and chatgpt.com on the web are unaffected.
Was my ChatGPT account or data compromised?
OpenAI states no evidence of user data access or system compromise. The Axios attack hit OpenAI’s Mac app build pipeline; the certificate is being rotated as a precaution, not in response to confirmed exfiltration.
Can I keep using ChatGPT after May 8 without updating?
The Mac app stops launching, but you can still use ChatGPT on the web at chatgpt.com, on iOS, on Android, or through any third-party Mac client (such as Fello AI app for Mac) that talks to OpenAI’s API rather than the official desktop binary.
