[macOS] In-app Browser unavailable because official 26.818.32112 helpers fail signature verification

Summary

The ChatGPT/Codex in-app Browser backend starts successfully on macOS, but the Browser client is rejected by the native pipe as untrusted-code-signing-identity. Browser discovery then returns an empty list and agent.browsers.get("iab") reports Browser is not available: iab.

The current official production DMG contains the same invalid signatures before installation. This does not appear to be local post-install corruption.

Environment

• ChatGPT desktop app: 26.818.32112
• CFBundleVersion: 6933
• Bundle identifier: com.openai.codex
• macOS: 26.6.2 (25G83)
• Architecture: Apple Silicon / arm64
• Browser plugin: browser@openai-bundled version 26.818.32112

Browser behavior

The desktop logs show the in-app Browser route registering and its backend becoming ready:

IAB_LIFECYCLE registered browser sidebar window
browser_use_iab_backend_startup_started backend=iab
browser_use_iab_backend_startup_ready backend=iab

When the bundled Browser client connects, the same log reports:

browser-use native pipe rejected socket peer reason=untrusted-code-signing-identity
dynamic_app_tools_peer_rejected reason=untrusted-code-signing-identity

The Browser runtime then reports:

await agent.browsers.list()
// []

await agent.browsers.get("iab")
// Browser is not available: iab

The issue persists after opening the built-in browser, restarting the desktop app, starting new threads, and reinstalling or refreshing the Browser plugin.

Signature verification

The installed app fails strict verification:

$ codesign --verify --deep --strict --verbose=4 /Applications/ChatGPT.app
/Applications/ChatGPT.app: invalid signature (code or signature have been modified)
In architecture: arm64

$ spctl --assess --type execute --verbose=4 /Applications/ChatGPT.app
/Applications/ChatGPT.app: internal error in Code Signing subsystem

The Browser-related executables fail independently:

/Applications/ChatGPT.app/Contents/Resources/cua_node/bin/node_repl: invalid signature
/Applications/ChatGPT.app/Contents/Resources/cua_node/bin/node: invalid signature
/Applications/ChatGPT.app/Contents/Resources/native/browser-use-peer-authorization.node: invalid signature
/Applications/ChatGPT.app/Contents/Resources/codex-code-mode-host: invalid signature

All report OpenAI TeamIdentifier 2DC432GLL2, but Authority=(unavailable).

Reproduced directly from the official DMG

Downloaded from the production URL embedded in the desktop app:

https://persistent.oaistatic.com/codex-app-prod/Codex.dmg

Downloaded artifact:

size: 654604560 bytes
SHA-256: 89fce961f1bbe172d73c508765bb906ea60575add66aefa3fb669cf8a478febb
hdiutil verify: VALID

The app was checked directly inside the read-only mounted DMG before copying or launching it. The untouched app and the same Browser helpers all failed codesign --verify --deep --strict with the identical invalid-signature result.

Expected behavior

The official production DMG should contain a ChatGPT app and bundled Browser helpers that pass strict macOS signature verification. The Browser native pipe should trust the bundled Browser client, register the iab backend, and allow the current desktop task to control the in-app browser.

Related reports

• #18523
• #37324
• #30545
• #33228

PR #39776 now verifies Desktop app signatures before launch or installation, but the production DMG served on 2026-08-21 still fails that verification.

No credentials, cookies, account identifiers, session IDs, private page contents, or application data are included in this report.

Start with PR #39776 and the production DMG at the reported URL; reproduce the failure using codesign --verify --deep --strict on the untouched app and Browser helpers. Trace the desktop release/signing path that produces these artifacts. Done means the official DMG and bundled helpers pass strict verification and the Browser native pipe accepts the client so iab is available.