CVE-2026-85660

cli-mcp-server 0.2.5 contains a command allowlist bypass vulnerability in the _validate_command_with_operators function when ALLOW_SHELL_OPERATORS is enabled. Attackers can use shell command substitution syntax like $(...) or backticks to execute non-allowlisted commands that bypass the ALLOWED_COMMANDS validation check.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/MladenSU/cli-mcp-server
https://github.com/MladenSU/cli-mcp-server/blob/main/src/cli_mcp_server/server.py
https://github.com/MladenSU/cli-mcp-server/issues/17
https://www.vulncheck.com/advisories/cli-mcp-server-0.2.5-command-allowlist-bypass-via-shell-substitution
https://github.com/MladenSU/cli-mcp-server/issues/17

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-04 15:17

Updated : 2026-09-04 18:18

NVD link : CVE-2026-85660

Mitre link : CVE-2026-85660

CVE.ORG link : CVE-2026-85660

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

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