CVE-2025-61591: Cursor CLI's Cursor Agent MCP OAuth2 Communication is Vulnerable to Remote Code Execution
Cursor is a code editor built for programming with AI. In versions 1.7 and below, when MCP uses OAuth authentication with an untrusted MCP server, an attacker can impersonate a malicious MCP server and return crafted, maliciously injected commands during the interaction process, leading to command injection and potential remote code execution. If chained with an untrusted MCP service via OAuth, this command injection vulnerability could allow arbitrary code execution on the host by the agent. This can then be used to directly compromise the system by executing malicious commands with full user privileges. This issue does not currently have a fixed release version, but there is a patch, 2025.09.17-25b418f.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2025-61591?
CVE-2025-61591 has a high severity rating due to the potential for an attacker to impersonate a malicious server.
How do I fix CVE-2025-61591?
To fix CVE-2025-61591, upgrade to Cursor versions beyond 1.7 where this vulnerability is addressed.
What are the risks associated with CVE-2025-61591?
The risks include unauthorized command execution and data exposure due to interaction with a malicious MCP server.
Which versions are affected by CVE-2025-61591?
Cursor versions 1.7 and below are affected by CVE-2025-61591.
Who is impacted by CVE-2025-61591?
Users of Cursor who rely on OAuth authentication with untrusted MCP servers are impacted by CVE-2025-61591.