{"schema":"threatline.record/2","record":{"id":"CVE-2026-55096","aliases":["GHSA-xr72-j7vj-vp7g"],"summary":"SSRF via DNS-resolution gap in _validate_url_security (file download by URL)","details":"fast-mcp-telegram is a Telegram MCP Server. Prior to version 30.1, the send_message/send_message_to_phone MCP tools accept files as a list of http(s) URLs, which the server downloads and attaches to the outgoing Telegram message. Downloads are guarded by _validate_url_security, an SSRF denylist that checks the URL's literal hostname string but never resolves DNS. The fetch (httpx.AsyncClient.get) does its own resolution at request time. Consequently a hostname that resolves to a loopback / private / link-local address passes the guard and is fetched — even with the secure defaults block_private_ips=True and allow_http_urls=False. Because the fetched body is returned to the attacker as a Telegram file attachment, this is a full-read, exfiltrating SSRF, not blind. This issue has been patched in version 30.1.","categories":["Unclassified"],"product":"fast-mcp-telegram","vendor":"leshchenko1979","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-55096","source_modified_at":"2026-10-01T14:39:11.027Z","fetched_at":"2026-10-23T18:52:38.922436Z","product":"fast-mcp-telegram","vendor":"leshchenko1979","versions":[{"version":"< 30.1","status":"affected"}],"defaultStatus":null}],"fixed_versions":[],"cvss":7.1,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00205,"percentile":0.09949,"score_date":"2026-10-23"},"published_at":"2026-09-28T16:38:26.730Z","modified_at":"2026-10-01T14:39:11.027Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-55096","fetched_at":"2026-10-23T18:52:38.922436Z","source_modified_at":"2026-10-01T14:39:11.027Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-55096","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/leshchenko1979/fast-mcp-telegram/security/advisories/GHSA-xr72-j7vj-vp7g","tags":["exploit"]},{"source":"CVE List","url":"https://github.com/leshchenko1979/fast-mcp-telegram/commit/e6b3032cfc906e14f5b84f2c2b8ec378eb457e57","tags":["x_refsource_MISC"]},{"source":"CVE List","url":"https://github.com/leshchenko1979/fast-mcp-telegram/releases/tag/0.30.1","tags":["x_refsource_MISC"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"poc","automatable":"no","technical_impact":"partial","assessed_at":"2026-10-01T14:38:52.830142Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":null,"confidence":"unknown","reviewed":false},"change_timestamp":"2026-10-01T14:39:11.027Z","content_hash":"75bd93bfe375b9138762a158e6f1def982300acfe53f4a18be80be21d67748e9"}}