CVE-2026-12940
CriticalCVSS 9.8Exploitation Probability (EPSS)
Elevated risk61th percentile - higher than 61% of all known CVEs
Summary
IBM Langflow OSS versions 1.0.0 through 1.10.1 are vulnerable to unauthenticated remote code execution via environment variable injection in the MCP stdio launcher. The vulnerability is due to an incomplete blocklist of dangerous environment variables (missing SHELLOPTS, BASHOPTS, and PS4) in src/lfx/src/lfx/base/mcp/util.py.
Risk Assessment
An unauthenticated attacker can remotely execute arbitrary code on the server, leading to full system compromise and potential data breach.
Recommendation
Immediately upgrade IBM Langflow OSS to version 1.10.2 or later, which includes a fix.
Other vulnerabilities in IBM Langflow OSS
See all- CVE-2026-93680Critical
IBM Langflow OSS versions 1.0.0 through 1.12.8 contain an improper authentication flaw that could allow a remote attacker to bypass security restrictions.
- CVE-2026-110186Critical
IBM Langflow OSS 1.0.0 through 1.12.8 could allow a remote attacker to execute arbitrary code due to improper control of code generation.
- CVE-2026-107329Critical
IBM Langflow OSS 1.0.0 through 1.12.4 could allow a remote authenticated attacker to execute arbitrary code due to improper control of code generation.
- CVE-2026-107328Critical
IBM Langflow OSS 1.0.0 through 1.12.4 could allow a remote authenticated attacker to execute arbitrary code due to improper neutralization of code in eval/exec.
- CVE-2026-107327Critical
IBM Langflow OSS versions 1.0.0 through 1.12.4 could allow a remote authenticated attacker to execute arbitrary code due to missing authorization.
- CVE-2026-104339Critical
IBM Langflow OSS versions 1.0.0 through 1.12.3 could allow a remote attacker to execute arbitrary code due to improper neutralization of special elements used in an OS command.
- CVE-2026-12944Critical
IBM Langflow OSS 1.0.0 through 1.10.0 allows attackers to execute arbitrary Python code with root privileges (UID=0) on the Langflow server by submitting components containing socket or urllib imports. This enables AWS credential theft via IMDSv1 SSRF, arbitrary file exfiltration from the container filesystem, and lateral movement to internal services (PostgreSQL, Redis) within the Docker network. The scanner incorrectly returns "validated": true, providing a false security signal.
- CVE-2026-81204Critical
IBM Langflow OSS versions 1.0.0 through 1.11.5 allow a remote attacker to execute arbitrary code due to code injection during graph construction.
- CVE-2026-79724Critical
IBM Langflow OSS versions 1.0.0 through 1.11.5 allow a remote attacker to execute arbitrary OS commands due to improper neutralization of special elements used in an OS command.
- CVE-2026-85025Critical
IBM Langflow OSS versions 1.0.0 through 1.11.5 allow an unauthenticated attacker to execute arbitrary code and access or modify chat sessions through publicly shared MCP project endpoints due to improper enforcement of public-flow security restrictions and session isolation controls.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS