{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-109427", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-10-12T15:52:36.681Z", "datePublished": "2026-10-12T20:35:49.858Z", "dateUpdated": "2026-10-12T20:35:49.858Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-10-12T20:35:49.858Z" }, "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. 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." } ], "tags": [ "x_open-source" ], "datePublic": "2026-10-02T00:00:00.000Z", "problemTypes": [ { "descriptions": [ { "lang": "en", "description": "Authorization Bypass Through User-Controlled Key", "cweId": "CWE-639", "type": "CWE" }, { "lang": "en", "description": "Missing Authorization", "cweId": "CWE-862", "type": "CWE" } ] } ], "affected": [ { "defaultStatus": "unaffected", "vendor": "weebzone", "product": "Telegram-Stremio", "packageURL": "pkg:github/weebzone/Telegram-Stremio", "repo": "https://github.com/weebzone/Telegram-Stremio", "versions": [ { "status": "affected", "version": "0", "versionType": "semver", "lessThanOrEqual": "5.1.0" } ] } ], "metrics": [ { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV4_0": { "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "subConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subAvailabilityImpact": "NONE", "exploitMaturity": "NOT_DEFINED", "Safety": "NOT_DEFINED", "Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "valueDensity": "NOT_DEFINED", "vulnerabilityResponseEffort": "NOT_DEFINED", "providerUrgency": "NOT_DEFINED", "version": "4.0", "baseSeverity": "HIGH", "baseScore": 7.1, "vectorString": "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" } }, { "format": "CVSS", "scenarios": [ { "lang": "en", "value": "GENERAL" } ], "cvssV3_1": { "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE", "version": "3.1", "baseSeverity": "MEDIUM", "baseScore": 6.5, "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N" } } ], "references": [ { "url": "https://gist.github.com/mansurmavlankulov/489554cad7b38e07b9651c217f00fffb", "name": "Researcher Disclosure", "tags": [ "technical-description" ] }, { "url": "https://www.vulncheck.com/advisories/telegram-stremio-broken-object-authorization-via-stream-ids", "name": "VulnCheck Advisory: Telegram-Stremio 5.1.0 Broken Object Authorization via Stream IDs", "tags": [ "third-party-advisory" ] } ], "credits": [ { "lang": "en", "value": "Mansurzhan Mavlankulov", "type": "finder" } ], "source": { "discovery": "UNKNOWN" }, "x_generator": { "engine": "vulncheck" } } } }