critical CVSS 9.9

CVE-2026-8481·Python vulnerability

IBM Langflow OSS 1.0.0 through 1.10.0 contain a critical remote code execution vulnerability in the code validation API endpoint. The POST /api/v1/validate/code endpoint accepts user-supplied Python code and executes it directly using Python's built-in exec() function without sandboxing, input validation, or privilege restrictions, enabling any authenticated user to execute arbitrary system commands with the full privileges of the Langflow server process.

Severity
critical
Software
Python
Fixed in
1.10.1
Published
2026-07-17

Affected versions

From: 1.0.0

Until: 1.10.1

Fixed in: 1.10.1

How to fix this CVE

Upgrade IBM Langflow OSS to version 1.10.1 or later to address a critical remote code execution vulnerability in the code validation API endpoint. Organizations running Langflow 1.0.0 through 1.10.0 should prioritize this update immediately, as the vulnerability allows authenticated users to execute arbitrary Python code on the server. Apply the patch through your package manager or container image update process within 48 hours.

sudo dnf update python3-langflow

Defensia detects this vulnerability

What an exploitation attempt looks like

Sample log line indicative of exploitation attempts:

POST /api/v1/validate/code HTTP/1.1.*exec\(|__import__|os\.system|subprocess|eval\(|open\(

WAF mitigation (if patching is not yet possible)

Add this rule to your WAF to block exploitation attempts while you schedule the patch. 

Restrict POST requests to /api/v1/validate/code endpoint to trusted internal networks only. Implement input validation to reject payloads containing Python keywords such as exec, import, __builtins__, subprocess, os.system, and eval. Alternatively, disable the endpoint entirely if not actively used.

How to check if you are affected

  1. Check installed Langflow version: pip show langflow | grep Version
  2. Verify the code validation endpoint is exposed: curl -s http://localhost:7860/api/v1/validate/code -X POST -H 'Content-Type: application/json' | head -20
  3. Search application logs for POST requests to /api/v1/validate/code: grep -i 'POST /api/v1/validate/code' /var/log/langflow/*.log /var/log/langflow/access.log 2>/dev/null
  4. Confirm the patch: pip show langflow | grep -E 'Version: 1\.(10\.[1-9]|[1-9][0-9])' && echo 'PATCHED' || echo 'VULNERABLE'

FAQ

What is CVE-2026-8481?

CVE-2026-8481 is a critical remote code execution flaw in IBM Langflow's code validation API that executes arbitrary Python code without proper sandboxing or input validation, allowing authenticated users to compromise the entire server.

Is CVE-2026-8481 being actively exploited?

No, this vulnerability is not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits have been released, but the critical severity warrants immediate patching.

What versions of Langflow are affected by CVE-2026-8481?

IBM Langflow OSS versions 1.0.0 through 1.10.0 are vulnerable; version 1.10.1 and later contain the fix.

How do I check if my server is vulnerable to CVE-2026-8481?

Run 'pip show langflow | grep Version' and verify the output is 1.10.1 or higher; if it shows any version from 1.0.0 to 1.10.0, your installation is vulnerable.

Does Defensia detect CVE-2026-8481?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Langflow is installed on a monitored server, CVE-2026-8481 will appear in your dashboard with remediation steps.

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References

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