CVE-2026-57860

ForgeCode (tailcallhq/forgecode), an AI pair-programming CLI, automatically loads and executes the MCP servers defined in a repository's .mcp.json file on startup without user confirmation. A malicious repository can supply a crafted .mcp.json whose mcpServers entries specify arbitrary command and args values (for example, command: bash with args: ['-c', 'touch /tmp/pwned']). When a user runs the forge CLI inside a cloned untrusted repository, the specified commands are spawned with the invoking user's privileges, resulting in arbitrary code execution. This provides a reliable initial-access and persistence primitive against developers who evaluate untrusted repositories with ForgeCode.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/tailcallhq/forgecode
https://github.com/tailcallhq/forgecode/commit/68ca3a3a26c73c38a700453d3d021b5bbdc15dbd
https://github.com/tailcallhq/forgecode/issues/3022
https://github.com/tailcallhq/forgecode/issues/3252
https://www.vulncheck.com/advisories/forgecode-arbitrary-code-execution-via-unvetted-mcp-json-in-untrusted-repository
https://github.com/tailcallhq/forgecode/issues/3022

Configurations

No configuration.

History

17 Jul 2026, 17:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-17 17:17

Updated : 2026-07-17 18:28

NVD link : CVE-2026-57860

Mitre link : CVE-2026-57860

CVE.ORG link : CVE-2026-57860

JSON object : View

Products Affected

No product.

CWE

CWE-829

Inclusion of Functionality from Untrusted Control Sphere

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