LockDown Browser + Little Snitch / Outbound Firewall on Mac

Last updated 2026-05-02 · LDBypass Editorial

Little Snitch and similar outbound firewalls (LuLu, Radio Silence) intercept network connections from every app on Mac. With default-deny rules, they block LDB's telemetry to Respondus servers. The two failure modes: connection-prompt mid-exam (Little Snitch dialog blocked by kiosk mode) and silent block of telemetry (your Monitor recording never reaches Respondus).

The symptom

Pre-exam: connection prompts from Little Snitch the first time LDB tries to reach Respondus. Mid-exam: dialog appears in front of LDB, intercepted by kiosk mode, triggers a violation event. Post-exam: instructor reports "no Monitor recording" - uploads were silently blocked.

Why it conflicts with LDB

Outbound firewalls implement default-deny for unfamiliar connections. LDB's connection to updates.respondus.com, config.respondus.com, and *.respondus.com is unfamiliar to your firewall on first launch. Without an explicit allow rule, the firewall either prompts or silently denies depending on configuration.

The fix - pre-exam procedure

Open Little Snitch Configuration (or your equivalent).
Add an explicit ALLOW rule:
- Process: Any
- Remote: *.respondus.com
- Port: TCP/443 (HTTPS)
- Action: Allow
Add a parallel rule for your LMS's domain if you don't have it already (e.g. *.canvas.com, *.blackboard.com).
Test by running your university's practice exam - the system check should complete without firewall prompts.
Verify the Monitor recording uploaded by checking with your instructor (some institutions provide a "recording uploaded" confirmation).

Alternative configurations

Less invasive options if you don't want to add permanent rules:

Disable Little Snitch entirely for the exam: Little Snitch menu → Pause Network Filter → for the next hour. Re-enable after.
Switch to Alert Mode: Little Snitch will prompt for every new connection but won't silently deny. The prompts may interfere with kiosk mode but at least nothing is silently blocked.
Whitelist your entire LDB session's connections: in Alert Mode, click "Allow until LDB quits" for each prompt during the practice exam. The rules are cached for the real exam.

What NOT to do

Don't try to bypass the conflict mid-exam - LDB's blacklist scan happens before exam launch and re-runs at intervals.
Don't restart the conflicting app DURING the exam - LDB will detect the new process and may flag.
Don't leave the conflicting app paused/disabled long-term outside exam windows; that's overkill for non-LDB use.

Frequently asked questions

Will silent block actually fail my exam?

Depends. The exam interface itself goes through your LMS, not Respondus directly. If Little Snitch blocks Respondus but allows your LMS, you can take the exam - but Monitor recording may not upload, leaving your instructor with no review material. Worst case: instructor flags you for "no recording".

Can I just disable Little Snitch permanently?

You can, but you're using Little Snitch for a reason (privacy/security). The whitelist approach preserves your privacy posture while letting LDB function.

What about the macOS built-in Application Firewall?

Apple's built-in firewall is inbound-only by default. Doesn't affect outbound connections. Doesn't conflict with LDB. Skip the worry.