CVE-2026-81097

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Source
https://cve.org/CVERecord?id=CVE-2026-81097
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81097.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-81097
Published
2026-08-27T14:50:37.617Z
Modified
2026-08-30T03:48:21.922095512Z
Severity
  • 8.6 (High) CVSS_V4 - CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N CVSS Calculator
Summary
rails-mcp-server 1.4.0 through 1.6.0 OS Command Execution via execute_ruby PTY Escape
Details

The execute_ruby tool is documented as a read-only Ruby sandbox and is enforced by a pattern denylist together with replacements for the process-spawning methods on Kernel. The pseudo-terminal library's spawn entry points are neither in the denylist nor replaced, so a normal tool call could reach them and start a shell, executing commands as the account running the server and outside the guarded methods. The denylist was introduced with the tool in 1.4.0 and never covered those entry points through 1.6.0. Version 1.6.1 restricts the requires the sandbox permits to a data-only list and blocks dynamic dispatch to execution entry points; 2.0.0 removes the tool.

Database specific 
{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81097.json",
    "cwe_ids": [
        "CWE-78"
    ],
    "cna_assigner": "VulnCheck"
}
References

Affected packages

Git / github.com/maquina-app/rails-mcp-server

Affected ranges

Type
GIT
Repo
https://github.com/maquina-app/rails-mcp-server
Events
Introduced
8cdd206fd77bbcf2b63d75724169be1a04f80c30
Fixed
5cf6e882ea6fada395a406248d018915182e25b7
Database specific
Show details 
{
    "source": [
        "AFFECTED_FIELD",
        "DESCRIPTION"
    ],
    "extracted_events": [
        {
            "introduced": "1.4.0"
        },
        {
            "last_affected": "1.6.0"
        },
        {
            "introduced": "0"
        },
        {
            "fixed": "1.6.0"
        }
    ]
}

Affected versions

v1.*
v1.4.0
v1.4.1
v1.5.0
v1.5.1

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81097.json"