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        "state": "PUBLISHED",
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        "dateReserved": "2026-07-01T17:20:57.549Z",
        "datePublished": "2026-07-01T19:27:23.367Z",
        "dateUpdated": "2026-07-07T12:50:17.730Z"
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            "title": "NodeBB - ActivityPub Author Spoofing via Unvalidated attributedTo Mapped to Local User",
            "descriptions": [
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                    "lang": "en",
                    "value": "NodeBB does not bind the claimed author of an inbound ActivityPub object to the authenticated remote actor. The inbound middleware verifies the HTTP-signature actor and checks the origin of object.id, but never validates that attributedTo corresponds to the sender. In the object mock, attributedTo is used directly as a uid, and actors.assert silently ignores numeric identifiers (filtering them out without re-deriving the uid), so a federated remote actor can set attributedTo to a bare numeric value such as 1 and have the resulting post or private message created with that local uid as author, including the administrator account. This lets a remote attacker forge posts and direct messages attributed to arbitrary local users. Requires the ActivityPub/federation feature to be enabled."
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            "datePublic": "2026-07-01T00:00:00.000Z",
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                            "lang": "en",
                            "cweId": "CWE-345",
                            "description": "Insufficient Verification of Data Authenticity",
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                            "lang": "en",
                            "cweId": "CWE-290",
                            "description": "Authentication Bypass by Spoofing",
                            "type": "CWE"
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            "affected": [
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                    "vendor": "NodeBB",
                    "product": "NodeBB",
                    "defaultStatus": "affected",
                    "versions": [
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                            "version": "4.13.2",
                            "status": "affected",
                            "versionType": "semver"
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                        "privilegesRequired": "NONE",
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                        "scope": "UNCHANGED",
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                        "Safety": "NOT_DEFINED",
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                    "name": "VulnCheck Advisory: NodeBB - ActivityPub Author Spoofing via Unvalidated attributedTo Mapped to Local User",
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