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CVE-2026-91931

Status: DeferredCritical (9)—

Flowise before 3.1.4 contains a remote code execution vulnerability in the Custom MCP node that allows authenticated attackers to execute arbitrary code by supplying npx package names in the mcpServerConfig parameter. Attackers can invoke npx with attacker-controlled npm packages to execute code on the Flowise server.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

AV:N/PR:L sin UI:R indica servicio remoto que requiere autenticación. CWE-78 (command injection) permite ejecutar código arbitrario vía npx con paquetes npm controlados por el atacante. El acceso a privilegios elevados del servidor Flowise implica posible escalada.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Threat Intelligence ProgramPrivileged Account ManagementExecution PreventionDisable or Remove Feature or ProgramApplication Isolation and SandboxingExploit Protection

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Flowiseai — FlowiseAI

CWEs

References

Raw JSON (NVD)

Show
{
  "id": "CVE-2026-91931",
  "cveTags": [],
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          "options": [
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          "version": "2.0.3",
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          "packageURL": "pkg:npm/flowise-components",
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  "published": "2026-09-15T16:17:43.883",
  "references": [
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    }
  ],
  "lastModified": "2026-09-23T17:17:47.090",
  "sourceIdentifier": "disclosure@vulncheck.com"
}