Public incident report: Codex Windows in-app Browser can trigger Code Integrity 3033, GPU crash, and an unreopenable task

[wdnmddmndw-design]

Public incident report

I am publishing an independently reproduced Windows crash so affected users and maintainers can correlate the failure. The same root symptom is tracked in #34133 and #35897; this post adds a different Windows build, AMD GPU, Codex package version, a timestamp-aligned evidence chain, and a validated local recovery.

User-visible impact

• After Codex automatically opened a webpage and Browser Use attempted a CDP screenshot, the desktop app exited.
• Windows then reported that the app could not be opened and required Repair.
• Reopening the same persisted task after repair caused the crash loop to recur.
• Project files were not corrupt. The trigger was restored in-app-browser state associated with the task.

Independently observed failure chain

Local time: China Standard Time (UTC+8).

1. 2026-07-30 00:19:52 - Browser Use logged Unable to capture screenshot for executeCdp:Page.captureScreenshot.
2. 2026-07-30 00:19:57 - Windows Code Integrity Event 3033 rejected the packaged vk_swiftshader.dll for ChatGPT.exe because it did not meet the Microsoft signing-level requirement.
3. At the same second, Codex logged the Chromium GPU child as reason=crashed with exitCode=101457950, followed by reason=launch-failed with exitCode=18.
4. Windows repeatedly repaired/re-registered the AppX package before Microsoft Store installed the newer build.

Environment

• Windows 11 Pro 10.0.26200 x64
• Crash package: OpenAI.Codex 26.721.4979.0
• Package after Store repair/update: OpenAI.Codex 26.721.11231.0
• GPU: AMD Radeon RX 6750 GRE 12GB
• Driver: 32.0.21045.1000 (2026-07-23)
• No nearby display-driver reset event
• No WER application-crash record or Crashpad report

The current package's vk_swiftshader.dll has no embedded Authenticode signature. The running GPU child reports MicrosoftSignedOnly=ON and AllowStoreSignedBinaries=OFF. I did not deliberately reproduce the crash on 26.721.11231.0 because another occurrence could make the app unusable again.

Recovery that worked locally

• Microsoft Store repair/update restored the package to Status: Ok.
• The bundled Browser plugin was temporarily disabled.
• Persisted thread-browser-tabs-v1 restoration records were removed while preserving tasks, attachments, and project files.
• The previously crashing task then reopened and remained responsive; no new Code Integrity 3033 event appeared during that validation.

This is a containment workaround, not a product fix.

Requested product behavior

If SwiftShader cannot load under the GPU-child signing policy, Browser Use should fall back safely. A recoverable GPU-child failure must not terminate the desktop app or make a persisted task impossible to reopen.

Evidence and privacy

A minimized ZIP is attached. It contains the full written report, a redacted Codex crash excerpt, the sanitized Code Integrity 3033 event, and environment/mitigation details.

• ZIP SHA-256: 7485B3231D02289EBC39C9B62EFBD2CE368B31009CC2D41997491086443D763E
• Omitted: prompts, visited URLs, account data, tokens, user-profile paths, conversation IDs, and browser IDs
• The unredacted original logs remain local.
  codex-windows-browser-gpu-crash-evidence-2026-07-30.zip