Bug 314116

Summary: [Site Isolation] Popup's inherited origin lost during didCommitLoad
Product: WebKit Reporter: roberto_rodriguez2
Component: New BugsAssignee: roberto_rodriguez2
Status: RESOLVED FIXED    
Severity: Normal CC: webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   

roberto_rodriguez2
Reported 2026-05-05 13:16:13 PDT
A popup opened via window.open() inherits its opener's origin during frame construction. When the about:blank document commits, didCommitLoad calls updateDocumentSecurityOrigin(nullptr) which overwrites the inherited origin with an opaque one because the creator reference is not retained. The opaque origin propagates to cross-origin processes via FrameTreeSyncData and Page::mainFrameOrigin(), causing the sandbox exemption in isNavigationBlockedByThirdPartyIFrameRedirectBlocking to fail because it can't verify the parent is same-origin with the top frame, so navigations from sandboxed allow-top-navigation iframes are incorrectly blocked.
Attachments
Radar WebKit Bug Importer
Comment 1 2026-05-05 13:16:19 PDT
roberto_rodriguez2
Comment 2 2026-05-05 13:21:27 PDT
EWS
Comment 3 2026-05-08 21:52:52 PDT
Committed 312937@main (14926e2a2447): <https://commits.webkit.org/312937@main> Reviewed commits have been landed. Closing PR #64292 and removing active labels.
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