Sample
rack-protection 4.2.1: Prevent Rack::Protection::AuthenticityToken from denying safe GET requests when session middleware is absent, while validating masked and unmasked CSRF tokens on unsafe requests
Verified sample for gem rack-protection 4.2.1: Prevent Rack::Protection::AuthenticityToken from denying safe GET requests when session middleware is absent…
sha256:cbdc3c3ea3ec557a27fc8fb08067ec858f4e4f30056c1856d23e37bef67466a5
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
- 1
Declared environment
ruby linux x64 ruby ruby rubygems
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| ruby 3 · linux alpine/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · rubygems@1 |
2026-08-16 |
| ruby 3 · linux debian/x64 · docker ed25519:2175b912ea1c23b1 | SKIPPED | compile:SKIPPED · contract:SKIPPED · load:SKIPPED · resolve:FAIL CONTAINER_RUN · rubygems@1 |
2026-08-18 |
Case
HOW- Goal
- Prevent Rack::Protection::AuthenticityToken from denying safe GET requests when session middleware is absent, while validating masked and unmasked CSRF tokens on unsafe requests
- Packages
- Symbols
-
- Rack::Protection::AuthenticityToken
- Rack::Protection::AuthenticityToken.token
- Environment
- ruby
- Created
- 2026-08-16T16:29:45Z
Contract
- AuthenticityToken responds with 403 Forbidden on safe GET requests when env lacks rack.session
- AuthenticityToken populates session[:csrf] with a 44-character Base64 token on valid GET requests
- AuthenticityToken accepts BREACH-mitigated 88-character masked tokens generated via AuthenticityToken.token
- AuthenticityToken accepts raw unmasked tokens matching session[:csrf] over HTTP_X_CSRF_TOKEN
- AuthenticityToken rejects unsafe POST requests with invalid tokens with 403 Forbidden and text/plain body
- AuthenticityToken restricts path-scoped per-form tokens strictly to matching request paths
Files
- Gemfile
- NOTES.md
- csx.json
- test/contract.rb