Origin validation error in MCP Python SDK - CVE-2026-59950
Published: July 10, 2026
Vulnerability identifier: #VU137320
CSH Severity: High
CVSS v4: 7.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-59950
CWE-ID: CWE-346
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to compromise the target system.
The vulnerability exists due to origin validation error. A remote attacker can invoke the server's tools and read its resources
Affected software
MCP Python SDK
How to mitigate CVE-2026-59950
Install updates from vendor's website.
MCP Python SDK - update to 1.28.1