Vulnerability Description
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.
CVSS Score
HIGH
Related Weaknesses (CWE)
References
- https://github.com/transmission/transmission
- https://github.com/transmission/transmission/blob/4.1.2/libtransmission/rpc-serv
- https://github.com/transmission/transmission/commit/c6a1bd2017a0fea9c956737c213f
- https://github.com/transmission/transmission/pull/8938
- https://github.com/transmission/transmission/releases/tag/4.1.3
- https://joshua.hu/transmission-cors-rpc-csrf-rce-drive-by-exploit
- https://www.vulncheck.com/advisories/transmission-4.0.0-before-4.1.3-permissive-
FAQ
What is CVE-2026-116748?
CVE-2026-116748 is a vulnerability with a CVSS score of 8.8 (HIGH). 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 we...
How severe is CVE-2026-116748?
CVE-2026-116748 has been rated HIGH with a CVSS base score of 8.8/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-116748?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.