Cursor Agent is vulnerable to prompt injection via MCP Special Files

CVE Details

Basic Information

Title Cursor Agent is vulnerable to prompt injection via MCP Special Files
Type cve
Published 2025-08-05T00:11:07.363Z
Modified 2025-08-05T00:11:07.363Z

Product Information

Vendor cursor
Product cursor
Version < 1.3.9

CVSS Information

Base Score 8.6 (HIGH)
Attack Vector CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H

AI Analysis

AI Description Cursor allows unauthorized creation of certain files, potentially enabling remote code execution via prompt injection. Fixed in version 1.3.9.
AI Severity Critical
AI Vendor Cursor
AI Product Cursor
AI Version versions below 1.3.9

Affected Products

  • cursor cursor < 1.3.9

Additional Information

CWE List CWE-78, CWE-829
Source GitHub_M

Description

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.

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