CVE-2025-54135 — Cursor Agent is vulnerable to prompt injection via MCP Special Files
Cursor is a code editor built for programming with AI. Cursor allows writing in-workspace files with no user approval in versions below 1.3.9, If the file is a dotfile, editing …
Published: 2025-08-05 · CVSS: 8.6 · CVSS 3.1
Cursor is a code editor built for programming with AI. Cursor allows writing in-workspace files with no user approval in versions below 1.3.9, If the file is a dotfile, editing it requires approval but creating a new one doesn't. Hence, if sensitive MCP files, such as the .cursor/mcp.json file don't already exist in the workspace, an attacker can chain a indirect prompt injection vulnerability to hijack the context to write to the settings file and trigger RCE on the victim without user approval. This is fixed in version 1.3.9.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7