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… OTP verify Because: * 6-digit OTP codes are vulnerable to distributed brute-force without email-scoped limits * We need production data on per-email verification volume before switching from report to block mode This commit: * Add passwordlessVerifyOtp email-scoped rule (10 per 10min, report) * Add passwordlessVerifyOtpPerDay email-scoped rule (20 per 24h, report) Closes #FXA-13331
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Pull request overview
This PR expands the FxA auth-server’s Customs v2 rate-limit configuration to add email-scoped, report-only monitoring for passwordless OTP verification attempts, enabling better visibility into abuse patterns without changing enforcement behavior.
Changes:
- Add a report-only
emailrule forpasswordlessVerifyOtp(10 attempts / 10 minutes, 30 minute cooldown). - Add a report-only
emailrule forpasswordlessVerifyOtpPerDay(20 attempts / 24 hours, 24 hour cooldown).
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StaberindeZA
approved these changes
Apr 8, 2026
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Because
This pull request
passwordlessVerifyOtpemail-scoped rule: 10 attempts per 10 minutes, 30 minute cooldown, report-onlypasswordlessVerifyOtpPerDayemail-scoped rule: 20 attempts per 24 hours, 24 hour cooldown, report-onlyrate-limit-rules.txtsit alongside the existingip_emailblock rules andipban rulesIssue that this pull request solves
Closes: https://mozilla-hub.atlassian.net/browse/FXA-13331
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