{"id":"CVE-2026-109427","state":"PUBLISHED","title":"Telegram-Stremio 5.1.0 Broken Object Authorization via Stream IDs","description":"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.","publishedAt":"2026-10-12T20:35:49.858Z","updatedAt":"2026-10-26T20:33:54.245Z","severity":{"score":7.1,"label":"High","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N","source":"VulnCheck"},"assigner":"VulnCheck","products":["weebzone Telegram-Stremio"],"affected":[{"vendor":"weebzone","product":"Telegram-Stremio","packageURL":"pkg:github/weebzone/Telegram-Stremio","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"5.1.0","versionType":"semver"}],"repo":"https://github.com/weebzone/Telegram-Stremio"}],"references":["https://gist.github.com/mansurmavlankulov/489554cad7b38e07b9651c217f00fffb","https://www.vulncheck.com/advisories/telegram-stremio-broken-object-authorization-via-stream-ids"],"weaknesses":["CWE-639","CWE-862"],"ingestedAt":"2026-10-29T20:10:33.477Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/109xxx/CVE-2026-109427.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-109427","state":"PUBLISHED","datePublished":"2026-10-12T20:35:49.858Z","dateUpdated":"2026-10-26T20:33:54.245Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-10-12T15:52:36.681Z"},"containers":{"cna":{"title":"Telegram-Stremio 5.1.0 Broken Object Authorization via Stream IDs","descriptions":[{"lang":"en","value":"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. 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