Cursor's Modification of MCP Server Definitions Bypasses Manual Re-approvals

Description

Cursor is a code editor built for programming with AI. In versions 1.2.4 and below, attackers can achieve remote and persistent code execution by modifying an already trusted MCP configuration file inside a shared GitHub repository or editing the file locally on the target's machine. Once a collaborator accepts a harmless MCP, the attacker can silently swap it for a malicious command (e.g., calc.exe) without triggering any warning or re-prompt. If an attacker has write permissions on a user's active branches of a source repository that contains existing MCP servers the user has previously approved, or allows an attacker has arbitrary file-write locally, the attacker can achieve arbitrary code execution. This is fixed in version 1.3.

Scores

EPSS (exploitation in 30 days)

31.5% · top 1.7% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: total

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.2.

Weakness

• CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (opens in a new tab)All about CWE-78 and its CVEs

Affected products

• cursor · cursor

  • affected < 1.3

References (1)

• https://github.com/cursor/cursor/security/advisories/GHSA-24mc-g4xr-4395 (opens in a new tab)x_refsource_CONFIRM

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2025-54136](https://trackcve.app/badge/CVE-2025-54136.svg)](https://trackcve.app/cve/CVE-2025-54136)

Record last updated 4 Aug 2025, 17:16 UTC.