{"schema":"threatline.record/2","record":{"id":"CVE-2026-109427","aliases":[],"summary":"Telegram-Stremio 5.1.0 Broken Object Authorization via Stream IDs","details":"Telegram-Stremio through 5.1.0 contains a broken object-level authorization vulnerability that allows authenticated token holders to access arbitrary chat messages by forging unsigned, unauthenticated stream IDs decoded via encode_string/decode_string functions. Attackers can craft or enumerate sequential msg_id values and set a global flag in the stream_handler endpoint to route requests through the operator's personal Userbot account, exposing private channels, groups, and Saved Messages, while the unauthenticated thumb_handler endpoint further discloses thumbnails from those same chats without any token validation.","categories":["Unclassified"],"product":"Telegram-Stremio","vendor":"weebzone","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-109427","source_modified_at":"2026-10-12T20:35:49.858Z","fetched_at":"2026-10-23T18:48:36.087640Z","product":"Telegram-Stremio","vendor":"weebzone","versions":[{"status":"affected","version":"0","versionType":"semver","lessThanOrEqual":"5.1.0"}],"defaultStatus":"unaffected"}],"fixed_versions":[],"cvss":7.1,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00209,"percentile":0.10422,"score_date":"2026-10-23"},"published_at":"2026-10-12T20:35:49.858Z","modified_at":"2026-10-12T20:35:49.858Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-109427","fetched_at":"2026-10-23T18:48:36.087640Z","source_modified_at":"2026-10-12T20:35:49.858Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-109427","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://gist.github.com/mansurmavlankulov/489554cad7b38e07b9651c217f00fffb","tags":["technical-description"]},{"source":"CVE List","url":"https://www.vulncheck.com/advisories/telegram-stremio-broken-object-authorization-via-stream-ids","tags":["third-party-advisory"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-12T20:35:49.858Z","content_hash":"edc935ec5005795f024624a222b8a037243d5db23b819b6e30ecbc7dcf189a1e"}}