Langflow: PythonREPLComponent executes unsandboxed Python code, enabling authenticated RCE and privilege escalation

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

9.9 · CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

• CVE-2026-10561: 0.82% estimated exploitation activity in the next 30 days; percentile 57.33 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Langflow's built-in Python interpreter components — PythonREPLComponent (Python Interpreter) and the legacy PythonREPLToolComponent (Python REPL Tool) — executed arbitrary user- or model-supplied Python code inside flows without effective sandboxing. Because the code ran in-process with the privileges of the Langflow service, any authenticated user who could edit and run a flow could achieve remote code execution and, from there, escalate privileges to superuser (e.g. by opening a database session and flipping issuperuser) or compromise the host. This issue is fixed as of 1.10.1, with additional hardening through 1.12.3. See Remediation below. Affected - Package: langflow (PyPI), and the underlying lfx package that ships the component. - Vulnerable versions: < 1.10.1. - Patched: 1.10.1 (core fix). Upgrade to = 1.12.3 for the complete hardening series. Details The root cause is code injection (CWE-94/CWE-95): the component passed raw input to LangChain's PythonREPL, which is…

Published by the source

6 Oct 2026, 13:38 UTC

Last modified by the source

15 Oct 2026, 14:56 UTC

Source last checked

26 Oct 2026, 13:55 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-8qpj-27x8-pwpq

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GHSA-8qpj-27x8-pwpq

3. Revision 1 · created · 23 Oct 2026

   Published from ghsa record GHSA-8qpj-27x8-pwpq

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# Patch Next advisory brief: CVE-2026-10561

Advisory: Langflow: PythonREPLComponent executes unsandboxed Python code, enabling authenticated RCE and privilege escalation
IDs: CVE-2026-10561, GHSA-8qpj-27x8-pwpq
Record: https://patchnext.com/advisories/cve-2026-10561 (revision 3, source checked 26 Oct 2026, 13:55 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Critical (CVSS 9.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: langflow 1.10.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- PyPI langflow: affected < 1.10.1; fixed in 1.10.1

## Suggested inspection (read-only)
- `python -m pip show langflow`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on langflow.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-8qpj-27x8-pwpq (GitHub-reviewed advisory GHSA-8qpj-27x8-pwpq lists affected ranges: PyPI langflow >=0 <1.10.1)
- Verified: https://osv.dev/vulnerability/GHSA-8qpj-27x8-pwpq (OSV record GHSA-8qpj-27x8-pwpq lists affected ranges: PyPI langflow >=0 <1.10.1 (fixed))

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