{"api_version":"1","generated_at":"2026-04-21T14:08:23+00:00","cve":"CVE-2026-35208","urls":{"html":"https://cve.report/CVE-2026-35208","api":"https://cve.report/api/cve/CVE-2026-35208.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-35208","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-35208"},"summary":{"title":"lichess.org has an Unsanitized Stream Title Injection on /streamer","description":"lichess.org is the forever free, adless and open source chess server. Any approved streamer can inject arbitrary HTML into /streamer and the homepage “Live streams” widget by placing markup in their Twitch/YouTube stream title. CSP is present and blocks inline script execution, but the issue is still a server-side HTML injection sink. To trigger this, a Lichess account only needs to satisfy the normal streamer requirements and get approved. Per Streamer.canApply, that means an account older than 2 days with at least 15 games, or a verified/titled account. After moderator approval, once the streamer goes live, Lichess pulls the platform title and renders it into the UI as-is. No extra privileges are needed beyond a normal approved streamer profile. 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