# privacypass/challenge-bypass-extension

DEPRECATED - Client for Privacy Pass protocol providing unlinkable cryptographic tokens

Repository: https://github.com/privacypass/challenge-bypass-extension
Canonical: https://ross.abutalabs.com/products/challenge-bypass-extension
Homepage: https://privacypass.github.io
Language: JavaScript
License: BSD-3-Clause
License Family: permissive
Topics: privacy-pass, cryptography, voprf, unlinkability, captcha, chrome-extension, browser-extension, privacy, token
Last push: 2025-02-17T12:05:34+00:00

## Health v2 (maintenance only)
Score: 26/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 7, release rhythm 8, longevity 100
- inputs: {"age_days": 3227, "days_push": 562, "days_rel": null, "gap_med": null, "n_releases_24m": 0}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 1250, forks 188 (observed 2026-08-28T04:04:08.084617+00:00)

## What it is
A browser extension implementing the client side of the Privacy Pass protocol, which issues and redeems unlinkable cryptographic tokens (based on VOPRFs) so users can bypass CAPTCHA challenges, e.g. on Cloudflare-protected sites, without solving them. The project is deprecated and no longer under active development.

## Use cases
- bypass cloudflare captchas automatically
- redeem privacy pass tokens instead of solving captchas
- browse websites anonymously without repeated captcha challenges
- get unlinkable cryptographic tokens after solving a captcha
- avoid captcha fatigue on protected websites

## When to choose
- you need a client for Privacy Pass providers like Cloudflare or hCaptcha
- you want to study or fork a reference implementation of the Privacy Pass protocol
- you value unlinkable, privacy-preserving captcha redemption

## When to avoid
- you need a maintained extension - this project is deprecated
- the website you visit does not support Privacy Pass providers
- you need server-side issuance or redemption logic rather than the browser client

## Facets
- artifact type: plugin
- maturity: abandoned
- function: cryptography, security, privacy
- domain: privacy, browser-extensions, security, censorship-circumvention
- platform: browser-extension, browser
- tags: privacy-pass, captcha-bypass, voprf, unlinkable-tokens, chrome-extension, firefox-addon, deprecated, javascript

## Member repositories
- privacypass/challenge-bypass-extension (main) score 26

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:04:08.084617+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 2026-08-30T05:07:45.226741+00:00, confidence not recorded.
  - readme: https://github.com/privacypass/challenge-bypass-extension (fetched 2026-08-28T04:04:08.084617+00:00, sha 11ba014e38f5)
  - homepage: https://privacypass.github.io (fetched 2026-08-29T12:18:46.772156+00:00, sha 0837d4e21f95)
- Data as of 2026-08-30T08:39:29.467469+00:00.