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.
Published: 2025-08-06
Cursor AI Editor is vulnerable to code execution via two flaws in how it handles MCP servers named "CurXecute" and "MCPoison."
https://www.darkreading.com/vulnerabilities-threats/rce-flaw-ai-coding-tool-supply-chain-risk
https://www.securityweek.com/several-vulnerabilities-patched-in-ai-code-editor-cursor/
https://thehackernews.com/2025/08/cursor-ai-code-editor-fixed-flaw.html
https://cyberscoop.com/cursor-ai-prompt-injection-attack-remote-code-privileges-aimlabs/
Published: 2025-08-05
Updated: 2025-08-05
Named Vulnerability: CurXecute
Base Score: 7.1
Vector: CVSS2#AV:N/AC:H/Au:S/C:C/I:C/A:C
Severity: High
Base Score: 8.5
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Severity: High
EPSS: 0.00047
Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.
Vulnerability Being Monitored