# Yawning/obfs4

The obfourscator (Courtesy mirror)

Repository: https://github.com/Yawning/obfs4
Canonical: https://ross.abutalabs.com/products/obfs4
Homepage: https://gitlab.com/yawning/obfs4
Language: Go
License: NOASSERTION
License Family: other
Last push: 2023-11-15T20:20:29+00:00

## Health v2 (maintenance only)
Score: 32/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 0, release rhythm 35, longevity 100
- inputs: {"age_days": 4499, "days_push": 1022, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: no_releases, no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1247, forks 194 (observed 2026-08-28T04:04:07.308537+00:00)

## What it is
obfs4 is a look-like-nothing traffic obfuscation protocol (the obfourscator) implemented in Go, based on ScrambleSuit with ntor handshakes and Elligator 2 key obfuscation. It ships as obfs4proxy, a pluggable transport for Tor that also supports obfs2/obfs3 and ScrambleSuit compatibility.

## Use cases
- run a Tor bridge that disguises its traffic as random noise
- connect to Tor bridges from censored networks
- deploy a pluggable transport proxy for circumventing DPI blocking
- act as an obfs2/obfs3 client or bridge for legacy compatibility

## When to choose
- you operate a Tor bridge and need traffic obfuscation resistant to deep packet inspection
- you need a battle-tested pluggable transport with mature cryptographic design

## When to avoid
- you need a general-purpose VPN or full traffic proxy rather than a Tor pluggable transport
- you need actively developed software with frequent releases

## Facets
- artifact type: library
- maturity: maintenance
- function: security, cryptography, proxy, networking
- domain: privacy, censorship-circumvention, security, networking
- platform: windows, go, cli
- tags: tor, obfuscation, pluggable-transport, bridge, anti-censorship, obfs4proxy, linux, macos

## Member repositories
- Yawning/obfs4 (main) score 32

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:07.308537+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-30T05:07:56.328593+00:00, confidence not recorded.
  - readme: https://github.com/Yawning/obfs4 (fetched 2026-08-28T04:04:07.308537+00:00, sha e32473f7e81e)
  - homepage: https://gitlab.com/yawning/obfs4 (fetched 2026-08-29T12:19:00.871418+00:00, sha 261e28980c3a)
- Data as of 2026-08-30T08:39:29.467469+00:00.