---
cve: "CVE-2026-12940"
severity: "CRITICAL"
cvss: 9.8
epss: "0.9%"
vendor: "IBM"
kev: false
exploited: false
published: "2026-07-30 17:16:28"
tags: [cve, security, critical]
source: tsecurity.de CVE-Dossier
exported: "2026-10-23T19:07:41+02:00"
---

# CVE-2026-12940

> 9.8 CRITICAL

## Beschreibung

IBM Langflow OSS 1.0.0 through 1.10.1  are vulnerable to unauthenticated remote code execution via environment variable injection in the MCP (Model Context Protocol) stdio launcher. The vulnerability exists in src/lfx/src/lfx/base/mcp/util.py where the DANGEROUS_ENV_VARS blocklist fails to include SHELLOPTS , BASHOPTS , and PS4 environment variables.

## CNA-Record (Kanon, cvelistV5)

- CNA: **ibm**
- State: PUBLISHED
- Stand: 2026-07-31 03:56:16
- CNA-CVSS: **9.8** (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)

## CISA-Anreicherung (vulnrichment/ADP)

- CISA-SSVC (Coordinator, v2.0.3):
  - Exploitation: **none**
  - Automatable: **yes**
  - Technical Impact: **total**

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Hoch | bad |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Hoch | bad |

## Schwachstellen-Klasse

- **CWE-78** — Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
  The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.

## Angriffsmuster (CAPEC)

- [CAPEC-6 — Argument Injection](https://capec.mitre.org/data/definitions/6.html) _(Severity: High)_
- [CAPEC-15 — Command Delimiters](https://capec.mitre.org/data/definitions/15.html) _(Severity: High)_
- [CAPEC-43 — Exploiting Multiple Input Interpretation Layers](https://capec.mitre.org/data/definitions/43.html) _(Severity: High)_
- [CAPEC-88 — OS Command Injection](https://capec.mitre.org/data/definitions/88.html) _(Severity: High)_
- [CAPEC-108 — Command Line Execution through SQL Injection](https://capec.mitre.org/data/definitions/108.html) _(Severity: Very High)_

## Patch verfügbar (OSV)

- a69a47ff1b5c99ce9c50edc4df45de4397151f17 (Commit)

## BSI-Hinweise (deutsch)

- [IBM Langflow Desktop: Mehrere Schwachstellen](https://wid.cert-bund.de/portal/wid/sicherheitshinweis/WID-SEC-W-2026-2366) — _BSI-Einstufung: hoch_
  Ein Angreifer kann mehrere Schwachstellen in IBM Langflow Desktop ausnutzen, um beliebigen Programmcode auszuführen, um Sicherheitsvorkehrungen zu umgehen, und um Informationen offenzulegen.

## Referenzen

- <https://www.ibm.com/support/pages/node/7279995>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/sicherheitsluecken/cve-2026-12940/) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI WID (CSAF)_