SSH sessions running `tmux` don't play back correctly in iTerm2

[webvictim]

Expected behavior

Teleport SSH recordings using tmux should play back correctly at the command line.

Current behavior

Playback halts in the terminal after tmux is invoked.

The session plays back OK in the 15.2.5 web UI, so I think this must be some kind of terminal issue.

I've attached an affected session recording (3b34a51c-a416-4aa6-902b-d334e9db9a4a.tar) to aid in debugging.

3b34a51c-a416-4aa6-902b-d334e9db9a4a.tar.zip

Bug details:

• Teleport version: 15.2.5

[webvictim]

session.end as requested (some values redacted):

{
  "addr.remote": "1.2.3.4:54861",
  "cluster_name": "purple",
  "code": "T2004I",
  "ei": 2159,
  "enhanced_recording": false,
  "event": "session.end",
  "interactive": true,
  "login": "ubuntu",
  "namespace": "default",
  "participants": [
    "webvictim"
  ],
  "private_key_policy": "none",
  "proto": "ssh",
  "server_addr": "[::]:3022",
  "server_hostname": "ip-172-31-30-140",
  "server_id": "1c4cf287-b8eb-43ad-a49a-d102efff1d7e",
  "server_labels": {
    "aws/Name": "example.teleportdemo.com",
    "aws/Owner": "gus",
    "aws/Purpose": "demo-server",
    "company": "acmecorp",
    "env": "aws",
    "external_ip": "5.6.7.8",
    "hostname": "ip-172-31-30-140",
    "region": "🇺🇸 us-east-2",
    "sysadmin": "true",
    "teleport-role": "auth,proxy,ssh,app,db",
    "version": "Teleport Enterprise v15.2.0 git:v15.2.0-0-gbb8bd77 go1.21.8"
  },
  "session_recording": "node",
  "session_start": "2024-04-30T15:21:18.793265555Z",
  "session_stop": "2024-04-30T15:22:40.491360934Z",
  "sid": "3b34a51c-a416-4aa6-902b-d334e9db9a4a",
  "time": "2024-04-30T15:22:40.492Z",
  "trusted_device": {
    "asset_tag": "123123123123",
    "credential_id": "eda45359-7377-40dc-9337-46076afc9ec3",
    "device_id": "8f4560f8-f1cf-43bf-a78e-049fff39bb8d"
  },
  "uid": "375565c4-f818-4957-b720-e5b85b0c8e7d",
  "user": "webvictim",
  "user_kind": 1
}

[zmb3]

This session plays back fine for me with tsh on master. I'll try v15 next.

[zmb3]

Seems to be related to iTerm2 and its tmux integration. I have no problem playing the session back in other terminal emulators. I imagine iTerm sees "tmux" on the PTY and activates some custom logic.