CVE-2026-12940
Langflow is affected by remote code execution due to multiple unauthenticated and insufficiently authorized API endpoints
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.
INFO
Published Date :
July 30, 2026, 5:16 p.m.
Last Modified :
July 30, 2026, 7:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | CRITICAL | 9a959283-ebb5-44b6-b705-dcc2bbced522 | ||||
| CVSS 3.1 | CRITICAL | [email protected] | ||||
| CVSS 3.1 | CRITICAL | MITRE-CVE |
Solution
- Update IBM Langflow OSS to version 1.10.2 or later.
- Review and sanitize all environment variables used by the MCP stdio launcher.
- Implement strict validation for environment variables, especially those related to shell operations.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-12940.
| URL | Resource |
|---|---|
| https://www.ibm.com/support/pages/node/7279995 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-12940 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-12940
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-12940 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-12940 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 30, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-12940', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'yes'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-07-30T18:05:05.374910Z'} -
New CVE Received by [email protected]
Jul. 30, 2026
Action Type Old Value New Value Added Affected [{'cpes': ['cpe:2.3:a:ibm:langflow_oss:1.0.0:*:*:*:*:*:*:*', 'cpe:2.3:a:ibm:langflow_oss:1.10.1:*:*:*:*:*:*:*'], 'vendor': 'IBM', 'product': 'Langflow OSS', 'versions': [{'status': 'affected', 'version': '1.0.0', 'versionType': 'semver', 'lessThanOrEqual': '1.10.1'}]}] Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-78 Added Reference https://www.ibm.com/support/pages/node/7279995