Intel

CVE-2026-12940

langflow: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') (CVE-2026-12940)

criticalPoCEPSS 0.9%

Affected

  • langflow/langflow between 1.0.0..1.10.2

Description

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.

Source: NVD (NIST)cvelistv5BSI WID PortalBSI CSAF

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

langflowlangflow
1.0.0 – 1.10.2

Metrics

XIEM Effective CVSS
9.8
Source: nvd-v3
EPSS percentile
59.9 %
High — this CVE ranks above the median of all CVEs scored today (rank ≥ 36%).
KEV status
—
Show all metrics
Severity
critical
Priority score
101.35
Exploit maturity
PoC (publicly reported)
CVSS v3
9.8
EPSS score
0.9 %
Low — model estimates < 1% exploitation likelihood.
Published
2026-07-30 16:41 UTC
CWE
CWE-78

Weakness classes (CWE)

  • CWE-78Base

    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.

    cwe.mitre.org →

References & sources

Reanalysis & status changes

Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

  1. Initial Analysis2026-08-04 20:20 UTC· nvd@nist.gov
    • CPE Configuration: OR *cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:* versions from (including) 1.0.0 up to (excluding) 1.10.2
    • Reference Type: IBM Corporation: https://www.ibm.com/support/pages/node/7279995 Types: Vendor Advisory
  2. CVE Modified2026-07-30 19:17 UTC· 134c704f-9b21-4f2e-91b3-4a467353bcc0
    • SSVC: {"id":"CVE-2026-12940","role":"CISA Coordinator","options":[{"exploitation":"none"},{"automatable":"yes"},{"technical…

Linked advisories