Reject empty QR codes to close signup auth bypass#330
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MichaelZhao21 merged 2 commits intohackutd:masterfrom Apr 29, 2026
Merged
Reject empty QR codes to close signup auth bypass#330MichaelZhao21 merged 2 commits intohackutd:masterfrom
MichaelZhao21 merged 2 commits intohackutd:masterfrom
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Lgtm--for context this was found at LA Hacks by https://devpost.com/software/codebreaker-la.
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Description
The QR-code judge signup flow (
POST /api/qr/add) authorizes attendees by comparing a submitted codeagainst
options.QRCode(oroptions.TrackQRCodes[track]). Both default to""— so before an admingenerates a QR (or for any track that's never had one set), submitting
{"code": ""}satisfies"" != ""→ false and a judge is created with attacker-controlled name/email. Same bypass applies to/api/qr/checkand/api/qr/check/:track.Fixes #[Issue]
Fix: reject empty values explicitly at all three comparison sites in
AddJudgeFromQR,CheckQRCode,and
CheckTrackQRCode.Type of Change
Delete options that do not apply:
Is this a breaking change?