CVE-2026-81097
Last modified
CVE-2026-81097 is a high-severity vulnerability rated 8.4/10 on the CVSS scale. 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. EPSS estimates a 0.17% chance of exploitation in the next 30 days.
Description
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.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| maquina-app | rails-mcp-server | >= 1.4.0, <= 1.6.0 |
References
Timeline
- Published
- Last Modified
- Status
- Received
Frequently Asked Questions
What is CVE-2026-81097?
How severe is CVE-2026-81097?
How do I fix CVE-2026-81097?
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
Related CVEs from 2026
- CVE-2026-81091The proxy middleware in mcp-use's inspector forwards request…8.6
- CVE-2026-81092mcp-go accepted requests on its HTTP transports without chec…6.8
- CVE-2026-81093The get-html-skeleton tool fetched a URL the caller supplied…8.6
- CVE-2026-81094The mcp-router CLI served its MCP aggregator on every interf…9.1
- CVE-2026-81095pg-aiguide started its MCP HTTP transport without enabling t…6.8
- CVE-2026-81096ToolUniverse ran caller-supplied Python inside a sandbox tha…10
- CVE-2026-81098The Telnyx MCP server exposed its HTTP transport on every in…9.1
- CVE-2026-81099tiger-slack started its MCP HTTP transport without enabling …6.8
- CVE-2026-8110Incorrect permissions assignment in the agent of Ivanti Endp…7.8
- CVE-2026-81100tiger-gh-mcp-server started its MCP HTTP transport without e…6.8
- CVE-2026-81101The configure command accepted any endpoint URL and stored i…6.5
- CVE-2026-81102The Dash MCP server bound its listener to the loopback addre…3.1
Are you affected by CVE-2026-81097?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST
