CVE-2026-85660 (GCVE-0-2026-85660)
Vulnerability from cvelistv5 – Published: 2026-09-04 14:32 – Updated: 2026-09-04 17:50
VLAI
EPSS
VEX
Title
cli-mcp-server 0.2.5 Command Allowlist Bypass via Shell Substitution
Summary
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.
Severity
8.1 (High)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-04 17:50 UTC
CWE
- CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/MladenSU/cli-mcp-server/issues/17 | issue-tracking |
| https://github.com/MladenSU/cli-mcp-server | product |
| https://github.com/MladenSU/cli-mcp-server/blob/m… | technical-description |
| https://www.vulncheck.com/advisories/cli-mcp-serv… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| MladenSU | cli-mcp-server |
Affected:
0 , ≤ 0.2.5
(semver)
|
guessed |
Date Public
2026-06-05 00:00
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