{"api_version":"1","generated_at":"2026-08-02T15:14:42+00:00","cve":"CVE-2026-68581","urls":{"html":"https://cve.report/CVE-2026-68581","api":"https://cve.report/api/cve/CVE-2026-68581.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-68581","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-68581"},"summary":{"title":"Vikunja 0.22.0 through 2.3.0 Authentication Bypass via Principal ID Collision","description":"Vikunja versions 0.22.0 through 2.3.0 fail to validate the principal type in API token management. Because user IDs and link-share IDs are independent numeric sequences and both resolve through a generic web.Auth.GetID() interface, a link-share JWT whose numeric ID equals a target user's ID is treated as that user by the /api/v1/tokens endpoints. An authenticated attacker can obtain a target's numeric user ID via authenticated user search, then create link shares on an attacker-writable project until the link-share sequence reaches that value, and use the resulting link-share JWT to list, create, and delete the target user's API tokens (including issuing a new token with attacker-chosen scopes under the target's permissions). 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