CVE-2026-116748

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 v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/transmission/transmission
https://github.com/transmission/transmission/blob/4.1.2/libtransmission/rpc-server.cc#L560
https://github.com/transmission/transmission/commit/c6a1bd2017a0fea9c956737c213f23e4b0f7929e
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-cors-leaks-rpc-anti-csrf-token

Configurations

No configuration.

History

26 Oct 2026, 22:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-26 22:16

Updated : 2026-10-31 03:17

NVD link : CVE-2026-116748

Mitre link : CVE-2026-116748

CVE.ORG link : CVE-2026-116748

JSON object : View

Products Affected

No product.

CWE

CWE-942

Permissive Cross-domain Security Policy with Untrusted Domains

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