VS Code Codex dictation fails with HTTP 403 cloudflare_challenge

Finding: In one external report, the Codex VS Code extension openai.chatgpt version 26.1007.21434 on Windows (win32-x64) recorded audio for dictation, but the /transcribe request returned HTTP 403 Forbidden and the composer reported errorMessage cloudflare_challenge, so dictation stopped without text (https://github.com/openai/codex/issues/52706). This is an external report only; KFA did not reproduce it. Reported conditions: the reporter observed it on October 9, 2026 and says it worked the previous day. Exact Windows and VS Code versions were not collected. Steps: open Codex Chat in VS Code, click the microphone button in the composer, speak for several seconds, then stop recording (https://github.com/openai/codex/issues/52706). Reported log sequence: microphone_ready, first_audio, recording_started and stop_requested all occurred normally. Then an Error fetching entry showed httpStatus=403 statusText=Forbidden url=/transcribe, followed by a Composer dictation failure with cloudflare_challenge and stage=failed. This indicates, per the reporter's logs, that local audio capture worked and the failure occurred at the transcription request (https://github.com/openai/codex/issues/52706). What the reporter tried: restarting VS Code several times and signing out and back in did not help. For comparison, the ChatGPT desktop app dictation works on the same PC and network, and GitHub Copilot Chat dictation works in the same VS Code instance (https://github.com/openai/codex/issues/52706). These are comparisons that narrow the problem away from the microphone and general network, but they are not a confirmed cause or a fix. Cause and status: the reporter explicitly says the logs establish that the transcription request is challenged but the reason for the challenge is unknown. No maintainer confirmation, fix commit or release was present in the supplied content. The only comment is an automated bot suggesting possible duplicates #51923 and #51924, which were not reviewed here (https://github.com/openai/codex/issues/52706#issuecomment-6089832445). Diagnostic use: if you see the same pairing of successful recording stages with a 403 on /transcribe and cloudflare_challenge, it matches this report. Treat it as a server-side or edge challenge on the transcription request rather than a microphone problem, as a hypothesis based on the reporter's logs only. Fix status is UNKNOWN. Evidence is from a single user and has not been independently reproduced.