{"id":"UBUNTU-CVE-2026-116748","details":"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 409 handshake response and replay it to issue RPC calls, enabling script-torrent-done execution, download-dir changes, or torrent and data deletion.","modified":"2026-10-28T20:17:46.315859454Z","published":"2026-10-26T22:16:00Z","upstream":["CVE-2026-116748"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-116748"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-116748"},{"type":"REPORT","url":"https://github.com/transmission/transmission"},{"type":"REPORT","url":"https://github.com/cveproject/cvelistv5/tree/main/cves/2026/116xxx/cve-2026-116748.json"},{"type":"REPORT","url":"https://github.com/transmission/transmission/blob/4.1.2/libtransmission/rpc-server.cc#l560"},{"type":"REPORT","url":"https://github.com/transmission/transmission/commit/c6a1bd2017a0fea9c956737c213f23e4b0f7929e"},{"type":"REPORT","url":"https://github.com/transmission/transmission/pull/8938"},{"type":"REPORT","url":"https://github.com/transmission/transmission/releases/tag/4.1.3"},{"type":"REPORT","url":"https://joshua.hu/transmission-cors-rpc-csrf-rce-drive-by-exploit"},{"type":"REPORT","url":"https://nvd.nist.gov/vuln/detail/cve-2026-116748"},{"type":"REPORT","url":"https://www.vulncheck.com/advisories/transmission-4.0.0-before-4.1.3-permissive-cors-leaks-rpc-anti-csrf-token"}],"affected":[{"package":{"name":"transmission","ecosystem":"Ubuntu:16.04:LTS","purl":"pkg:deb/ubuntu/transmission?arch=source&distro=xenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.84-1ubuntu1","2.84-2","2.84-3","2.84-3ubuntu1","2.84-3ubuntu2","2.84-3ubuntu3","2.84-3ubuntu3.1"],"ecosystem_specific":{"binaries":[{"binary_name":"transmission","binary_version":"2.84-3ubuntu3.1"},{"binary_name":"transmission-cli","binary_version":"2.84-3ubuntu3.1"},{"binary_name":"transmission-common","binary_version":"2.84-3ubuntu3.1"},{"binary_name":"transmission-daemon","binary_version":"2.84-3ubuntu3.1"},{"binary_name":"transmission-gtk","binary_version":"2.84-3ubuntu3.1"},{"binary_version":"2.84-3ubuntu3.1","binary_name":"transmission-qt"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-116748.json"}},{"package":{"name":"transmission","ecosystem":"Ubuntu:18.04:LTS","purl":"pkg:deb/ubuntu/transmission?arch=source&distro=bionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.92-2ubuntu3","2.92-3ubuntu1","2.92-3ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"transmission","binary_version":"2.92-3ubuntu2"},{"binary_version":"2.92-3ubuntu2","binary_name":"transmission-cli"},{"binary_name":"transmission-common","binary_version":"2.92-3ubuntu2"},{"binary_version":"2.92-3ubuntu2","binary_name":"transmission-daemon"},{"binary_name":"transmission-gtk","binary_version":"2.92-3ubuntu2"},{"binary_version":"2.92-3ubuntu2","binary_name":"transmission-qt"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-116748.json"}},{"package":{"name":"transmission","ecosystem":"Ubuntu:20.04:LTS","purl":"pkg:deb/ubuntu/transmission?arch=source&distro=focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.94-2ubuntu1","2.94-2ubuntu2","2.94-2ubuntu3"],"ecosystem_specific":{"binaries":[{"binary_name":"transmission","binary_version":"2.94-2ubuntu3"},{"binary_name":"transmission-cli","binary_version":"2.94-2ubuntu3"},{"binary_version":"2.94-2ubuntu3","binary_name":"transmission-common"},{"binary_name":"transmission-daemon","binary_version":"2.94-2ubuntu3"},{"binary_name":"transmission-gtk","binary_version":"2.94-2ubuntu3"},{"binary_version":"2.94-2ubuntu3","binary_name":"transmission-qt"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-116748.json"}},{"package":{"name":"transmission","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/transmission?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.00-1ubuntu2","3.00-1ubuntu5","3.00-2ubuntu1","3.00-2ubuntu2","3.00-2ubuntu2.1","3.00-2ubuntu2.2"],"ecosystem_specific":{"binaries":[{"binary_version":"3.00-2ubuntu2.2","binary_name":"transmission"},{"binary_name":"transmission-cli","binary_version":"3.00-2ubuntu2.2"},{"binary_name":"transmission-common","binary_version":"3.00-2ubuntu2.2"},{"binary_name":"transmission-daemon","binary_version":"3.00-2ubuntu2.2"},{"binary_version":"3.00-2ubuntu2.2","binary_name":"transmission-gtk"},{"binary_version":"3.00-2ubuntu2.2","binary_name":"transmission-qt"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-116748.json"}},{"package":{"name":"transmission","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/transmission?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.0.2-1ubuntu3","4.0.5-1","4.0.5-1build3","4.0.5-1build4","4.0.5-1build5","4.0.5-1ubuntu0.1"],"ecosystem_specific":{"binaries":[{"binary_name":"transmission","binary_version":"4.0.5-1ubuntu0.1"},{"binary_name":"transmission-cli","binary_version":"4.0.5-1ubuntu0.1"},{"binary_version":"4.0.5-1ubuntu0.1","binary_name":"transmission-common"},{"binary_version":"4.0.5-1ubuntu0.1","binary_name":"transmission-daemon"},{"binary_version":"4.0.5-1ubuntu0.1","binary_name":"transmission-gtk"},{"binary_version":"4.0.5-1ubuntu0.1","binary_name":"transmission-qt"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-116748.json"}},{"package":{"name":"transmission","ecosystem":"Ubuntu:26.10","purl":"pkg:deb/ubuntu/transmission?arch=source&distro=stonking"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.1.1+dfsg-1ubuntu1","4.1.2+dfsg-1ubuntu1","4.1.3+dfsg-1ubuntu1","4.1.3+dfsg-1ubuntu2"],"ecosystem_specific":{"binaries":[{"binary_name":"transmission","binary_version":"4.1.3+dfsg-1ubuntu2"},{"binary_version":"4.1.3+dfsg-1ubuntu2","binary_name":"transmission-cli"},{"binary_name":"transmission-common","binary_version":"4.1.3+dfsg-1ubuntu2"},{"binary_name":"transmission-daemon","binary_version":"4.1.3+dfsg-1ubuntu2"},{"binary_name":"transmission-gtk","binary_version":"4.1.3+dfsg-1ubuntu2"},{"binary_version":"4.1.3+dfsg-1ubuntu2","binary_name":"transmission-qt"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-116748.json"}},{"package":{"name":"transmission","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/transmission?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["4.1.0~beta2+dfsg-3ubuntu1","4.1.0~beta2+dfsg-3ubuntu2","4.1.0~beta4+dfsg-1ubuntu1","4.1.0~beta5+dfsg-1ubuntu1","4.1.0+dfsg-1ubuntu1","4.1.1+dfsg-1ubuntu1","4.1.1+dfsg-1ubuntu1.1"],"ecosystem_specific":{"binaries":[{"binary_name":"transmission","binary_version":"4.1.1+dfsg-1ubuntu1.1"},{"binary_name":"transmission-cli","binary_version":"4.1.1+dfsg-1ubuntu1.1"},{"binary_name":"transmission-common","binary_version":"4.1.1+dfsg-1ubuntu1.1"},{"binary_name":"transmission-daemon","binary_version":"4.1.1+dfsg-1ubuntu1.1"},{"binary_version":"4.1.1+dfsg-1ubuntu1.1","binary_name":"transmission-gtk"},{"binary_name":"transmission-qt","binary_version":"4.1.1+dfsg-1ubuntu1.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-116748.json"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N"},{"type":"Ubuntu","score":"medium"}]}