uvicorn Uvicorn via gunicorn worker doesn't respect

The Fix

Upgrade to version 0.11.4 or later.

Based on closed Kludex/uvicorn issue #589 · PR/commit linked

Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.

Jump to Verify Open PR/Commit

@@ -2,6 +2,7 @@
 
 from gunicorn.workers.base import Worker
+
 from uvicorn.config import Config
 from uvicorn.main import Server

repro.py

gunicorn \
  ppm_telegram_bot.api:app \
  --forwarded-allow-ips="*" 
  --worker-class=uvicorn.workers.UvicornWorker \
  --bind=0.0.0.0:$PORT

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

fix.md

Option A — Upgrade to fixed release\nUpgrade to version 0.11.4 or later.\nWhen NOT to use: This fix should not be used if the application does not require accurate client IP forwarding.\n\nOption C — Workaround\n— set  `FORWARDED_ALLOW_IPS="*"` as env var before running gunicorn\nWhen NOT to use: This fix should not be used if the application does not require accurate client IP forwarding.\n\n

Why This Fix Works in Production

Trigger: Uvicorn via gunicorn worker doesn't respect `--forwarded-allow-ips`
Mechanism: Uvicorn worker does not respect Gunicorn's forwarded-allow-ips configuration, leading to incorrect client IP handling
Why the fix works: Adds support for the `forwarded-allow-ips` configuration to the gunicorn worker in Uvicorn, addressing issue #589. (first fixed release: 0.11.4).

Production impact:

If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.

Why This Breaks in Prod

Uvicorn worker does not respect Gunicorn's forwarded-allow-ips configuration, leading to incorrect client IP handling
Production symptom (often without a traceback): Uvicorn via gunicorn worker doesn't respect `--forwarded-allow-ips`

Proof / Evidence

GitHub issue: #589
Fix PR: https://github.com/kludex/uvicorn/pull/592
First fixed release: 0.11.4
Reproduced locally: No (not executed)
Last verified: 2026-02-09
Confidence: 0.85
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.75

Discussion

High-signal excerpts from the issue thread (symptoms, repros, edge-cases).

Jump to Sources Open on GitHub

“Current workaround — set FORWARDED_ALLOW_IPS="*" as env var before running gunicorn”

@b0g3r · 2020-03-16 · source

“The suggested change sounds legit to me @b0g3r, happy to review PRs. :-) Edit: oh there's already #592. 🤦”

@florimondmanca · 2020-04-10 · source

“I have kinda similar problem, I'd like actually to put proxy IP as forwarded-allow-ips, but when I do forwarded-allow-ips="mydomain.com" it doesn't work, I suppose that's…”

@PetrShchukin · 2021-03-18 · source

“Try "userland-proxy": false in /etc/docker/daemon.json, which makes it so the proxy can see the actual IP of the client rather than the Docker bridge.”

@merlinz01 · 2025-06-23 · source

Failure Signature (Search String)

Uvicorn via gunicorn worker doesn't respect `--forwarded-allow-ips`
Gunicorn has a special option to change proxy-ip to real-ip, so I running gunicorn like this:

Copy-friendly signature

signature.txt

Failure Signature
-----------------
Uvicorn via gunicorn worker doesn't respect `--forwarded-allow-ips`
Gunicorn has a special option to change proxy-ip to real-ip, so I running gunicorn like this:

Error Message

Signature-only (no traceback captured)

error.txt

Error Message
-------------
Uvicorn via gunicorn worker doesn't respect `--forwarded-allow-ips`
Gunicorn has a special option to change proxy-ip to real-ip, so I running gunicorn like this:

Minimal Reproduction

repro.py

gunicorn \
  ppm_telegram_bot.api:app \
  --forwarded-allow-ips="*" 
  --worker-class=uvicorn.workers.UvicornWorker \
  --bind=0.0.0.0:$PORT

What Broke

Requests receive incorrect client IPs, causing issues with client identification and logging.

Why It Broke

Uvicorn worker does not respect Gunicorn's forwarded-allow-ips configuration, leading to incorrect client IP handling

Fix Options (Details)

Option A — Upgrade to fixed release Safe default (recommended)

Upgrade to version 0.11.4 or later.

When NOT to use: This fix should not be used if the application does not require accurate client IP forwarding.

Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.

Option C — Workaround Temporary workaround

— set `FORWARDED_ALLOW_IPS="*"` as env var before running gunicorn

When NOT to use: This fix should not be used if the application does not require accurate client IP forwarding.

Use only if you cannot change versions today. Treat this as a stopgap and remove once upgraded.

Fix reference: https://github.com/kludex/uvicorn/pull/592

First fixed release: 0.11.4

Last verified: 2026-02-09. Validate in your environment.

When NOT to Use This Fix

This fix should not be used if the application does not require accurate client IP forwarding.

Verify Fix

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

Did This Fix Work in Your Case?

Quick signal helps us prioritize which fixes to verify and improve.

Prevention

Capture the exact failing error string in logs and tests so you can reproduce via a minimal script.
Pin production dependencies and upgrade only with a reproducible test that hits the failing path.

Version Compatibility Table

Version	Status
0.11.4	Fixed

Related Issues

No related fixes found.

Cluster: uvicorn:configuration-error All hubs All clusters

Related clusters: Data consistency Race condition SSL handshake

Sources

We don’t republish the full GitHub discussion text. Use the links above for context.

uvicorn Uvicorn via gunicorn worker doesn't respect `--forwarded-allow-ips` (Fix)