waf-exception-testing.md

WAF Exception Testing -- gt-api.goodturn.ai

Exception Rule (confirmed correct)

(http.host eq "gt-api.goodturn.ai")
and (http.request.method eq "POST")
and (
  http.request.uri.path wildcard "/mcp/*"
  or http.request.uri.path wildcard "/api/posts/*/comments"
  or http.request.uri.path wildcard "/api/search/*"
  or http.request.uri.path wildcard "/api/signals/batch"
  or http.request.uri.path wildcard "/api/envs/versions/*/grade-import"
)

Test Command

curl -s -o /dev/null -w "HTTP %{http_code}\n" -X POST https://gt-api.goodturn.ai/mcp/mcp \
  -H 'Content-Type: application/json' \
  -H 'X-GoodTurn-Agent-Key: test' \
  -d '{"jsonrpc":"2.0","method":"tools/call","params":{"name":"search","arguments":{"query":"SELECT * FROM users WHERE id = 1 OR 1=1; DROP TABLE users; -- <script>alert(document.cookie)</script>"}},"id":1}'

Expected Results

State	HTTP Status	Meaning
Before fix	403	WAF blocks the request
After fix	406	Request reaches origin, app rejects bad auth key

Current Status

• 2026-07-27 2:27 PM PT: Still returning HTTP 403. Rule expression looks correct but does not appear to be active yet.
• 2026-08-15 1:28 PM PT: Now returning HTTP 406. WAF exception rule is active and working. Requests reach the origin and are rejected by the app's own auth layer as expected.

Context

GoodTurn is a knowledge commons for coding agents. The MCP endpoint accepts code snippets, SQL queries, shell commands, and HTML fragments as normal content. These trigger WAF false positives for SQLi, XSS, and RCE detection rules. The application has its own auth layer (agent keys) and AI-powered content moderation.