CodeSampleX

Sample

httpx 0.28.1: Bypass proxy for IPv4 and IPv6 addresses in NO_PROXY without InvalidURL crashes or suffix match leaks as fixed in httpx 0.24.1

Verified sample for pypi httpx 0.28.1: Bypass proxy for IPv4 and IPv6 addresses in NO_PROXY without InvalidURL crashes or suffix match leaks as fixed in…

sha256:761a3183dc4134e0c3afbb49c328f365161fb775e1a73aab769c692dfa0ca8db

This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured. How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people. MIT-0

Execution evidence

The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.

Evidence basis
Signed contract pass
Verification receipts
2
Signing keys that built it
2
Declared environment python linux x64 python python pip

Verification-run environments

Environment Contract Stages Run
python 3.12 · linux alpine/x64 · docker ed25519:d91480838ac982c9 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · python@1
2026-08-16
python 3.12 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1 PASS compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS
CONTAINER_RUN · python@1
2026-08-18

Case

HOW
Goal
Bypass proxy for IPv4 and IPv6 addresses in NO_PROXY without InvalidURL crashes or suffix match leaks as fixed in httpx 0.24.1
Packages
Symbols
  • httpx.Client
  • httpx.AsyncClient
  • httpx._utils.get_environment_proxies
  • httpx._utils.URLPattern
  • httpx.InvalidURL
Environment
python
Created
2026-08-16T05:33:45Z

Contract

  1. assert get_environment_proxies mounts IPv4 as all://<ip>, IPv6 as all://[<ip>], and localhost as all://localhost without wildcard asterisk
  2. assert httpx.Client(trust_env=True) with NO_PROXY=::1 initializes without raising InvalidURL from malformed all://*::1 pattern
  3. assert client._transport_for_url routes IPv6 http://[::1]:8080 to direct transport when NO_PROXY contains ::1
  4. assert client._transport_for_url routes exact IPv4 http://127.0.0.1:8080 to direct transport when NO_PROXY contains 127.0.0.1
  5. assert client._transport_for_url routes attacker.example.invalid to proxy transport preventing suffix-matching bypass leaks
  6. assert client._transport_for_url routes not-localhost.example.invalid to proxy transport preventing suffix-matching bypass leaks

Files

  • NOTES.md
  • csx.json
  • requirements.lock
  • requirements.txt
  • src/__init__.py
  • src/proxy_env.py
  • test/__init__.py
  • test/contract.py

Download the source artifact (tar.gz)

Origin Seeder

csx-seed