CVE-2026-116748

Name	CVE-2026-116748
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.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
transmission (PTS)	bookworm	3.00-2.1+deb12u1	vulnerable
	trixie	4.1.0~beta2+dfsg-3+deb13u2	vulnerable
	forky, sid	4.1.3+dfsg-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
transmission	source	(unstable)	4.1.3+dfsg-1

Notes

https://github.com/transmission/transmission/pull/8938
Fixed by: https://github.com/transmission/transmission/commit/c6a1bd2017a0fea9c956737c213f23e4b0f7929e (4.1.3)