fix(authentication-oauth): prevent open redirect via domain suffix attack#3669
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ByamB4 wants to merge 1 commit intofeathersjs:dovefrom
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fix(authentication-oauth): prevent open redirect via domain suffix attack#3669ByamB4 wants to merge 1 commit intofeathersjs:dovefrom
ByamB4 wants to merge 1 commit intofeathersjs:dovefrom
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…tack The regex validation for the redirect query parameter blocked @, \, and // characters but did not prevent domain suffix attacks via . or - characters. For example, ?redirect=.attacker.com would produce https://target.com.attacker.com allowing an attacker to steal OAuth access tokens. Fix: require redirect parameter to be a relative path starting with /, which prevents all URL authority manipulation attacks. Co-Authored-By: Claude Opus 4.6 <[email protected]>
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Summary
redirectquery parameter in OAuth strategy@,\, and//but allows domain suffix attacks via.and-characters?redirect=.attacker.comproduceshttps://target.com.attacker.com, leaking the OAuth access token to an attacker-controlled domainChanges
queryRedirectto start with/(relative path only), preventing all URL authority manipulation attacks.attacker.com,-attacker.com, bare domain) and valid relative path redirectsAttack Vector
GET /oauth/google?redirect=.attacker.comhttps://target.com.attacker.com#access_token=JWT_TOKENtarget.com.attacker.com, they receive the victim's access tokenTest plan
@,\\,//rejection tests still pass.attacker.comdomain suffix attack is rejected-attacker.comdomain suffix attack is rejectedattacker.comredirect is rejected/dashboard,/callback?state=abc) still workRelated to the fix in #3663 (CVE-2026-27191).