Fix _checkOrigin() to require domain boundary check#123
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ScottHelme wants to merge 1 commit intolbuchs:masterfrom
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Fix _checkOrigin() to require domain boundary check#123ScottHelme wants to merge 1 commit intolbuchs:masterfrom
ScottHelme wants to merge 1 commit intolbuchs:masterfrom
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The suffix regex accepted lookalike domains (e.g. evil-example.com for RP ID example.com). Replace with exact match or dot-boundary subdomain check per W3C WebAuthn Level 2 spec §7.1 Step 5 / §7.2 Step 9.
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Summary
Fixes
_checkOrigin()to enforce a domain boundary when validating the origin against the RP ID, as required by the W3C WebAuthn Level 2 spec (§7.1 Step 5 / §7.2 Step 9).Problem
The existing regex
preg_match('/' . preg_quote($rpId) . '$/i', $host)matches any hostname ending with the RP ID string. For RP IDexample.com, lookalike domains likeevil-example.comandevilexample.comincorrectly pass validation.Fix
Replace the suffix regex with an exact match check (
strcasecmp) and a dot-boundary subdomain check (str_ends_withwith a.prefix). This acceptsexample.comandwww.example.comwhile rejectingevil-example.comandevilexample.com.Closes #122