{"id":"CVE-2026-116748","title":"Transmission 4.0.0 before 4.1.3 Permissive CORS Leaks RPC Anti-CSRF Token","summary":"Transmission 4.0.0 before 4.1.3 contains a permissive CORS vulnerability in handle_request() in rpc-server.cc that exposes the X-Transmission-Session-Id anti-CSRF token to any web origin. Malicious web pages can read the token from the 4…","severity":"high","cvss":8.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cvssSource":"cna","cwe":["CWE-942"],"vendor":"transmission","product":"transmission","affected":["transmission >= 4.0.0 < 4.1.3"],"published":"2026-10-26","updated":"2026-10-26","sourceUpdated":"2026-10-26T21:52:45.799Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-116748","references":[{"url":"https://github.com/transmission/transmission/pull/8938","label":"Pull Request #8938"},{"url":"https://github.com/transmission/transmission/commit/c6a1bd2017a0fea9c956737c213f23e4b0f7929e","label":"Patch Commit"},{"url":"https://github.com/transmission/transmission"},{"url":"https://github.com/transmission/transmission/releases/tag/4.1.3","label":"transmission 4.1.3 Release Notes"},{"url":"https://github.com/transmission/transmission/blob/4.1.2/libtransmission/rpc-server.cc#L560"},{"url":"https://joshua.hu/transmission-cors-rpc-csrf-rce-drive-by-exploit"},{"url":"https://www.vulncheck.com/advisories/transmission-4.0.0-before-4.1.3-permissive-cors-leaks-rpc-anti-csrf-token","label":"VulnCheck Advisory: Transmission 4.0.0 before 4.1.3 Permissive CORS Leaks RPC Anti-CSRF Token"}],"tags":["cve.org"],"epss":0.00527,"epssPercentile":0.44465,"ingestedAt":"2026-10-27T16:11:59.129Z","slug":"CVE-2026-116748","body":"## Overview\n\nTransmission 4.0.0 before 4.1.3 contains a permissive CORS vulnerability in handle_request() in rpc-server.cc that exposes the X-Transmission-Session-Id anti-CSRF token to any web origin. Malicious web pages can read the token from the 409 handshake response and replay it to issue RPC calls, enabling script-torrent-done execution, download-dir changes, or torrent and data deletion.\n\n## Affected\n\n- `transmission >= 4.0.0 < 4.1.3`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":49,"depthScoreParts":{"impact":48.4,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}