CVE-2026-33484: Langflow Langflow Has Unauthenticated IDOR On Vulnerability

HIGH
Advisory Identifier: GHSA-7grx-3xcx-2xv5
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CVSS 7.5
CWE-284 CWE-639 CWE-862
Published
Advisory Summary

CVE-2026-33484 is a HIGH (CVSS 7.5) langflow has unauthenticated idor on vulnerability (CWE-284: Improper Access Control) affecting Langflow libraries in the PyPI ecosystem. The issue involves langflow has unauthenticated idor on image downloads. Remediation is available by upgrading affected packages to version 1.9.0.

CVE-2026-33484 at a Glance

CVE Identifier CVE-2026-33484
GHSA Identifier GHSA-7grx-3xcx-2xv5
Severity HIGH
CVSS v3.1 Base Score 7.5
CWE Classification CWE-284: Improper Access Control
Affected Product Langflow
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 7.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2026-33484

To remediate this vulnerability, upgrade all affected Langflow dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

langflow fixed: 1.9.0 
pip install langflow>=1.9.0
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show langflow

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2026-33484, inspect your installed packages using pip:

pip show langflow

Analyze the terminal output to locate any version of Langflow in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.9.0), your application is affected.

Note: The pip show langflow command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-284: Improper Access Control, where the product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. In Langflow, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Summary The `/api/v1/files/images/{flow_id}/{file_name}` endpoint serves image files without any authentication or ownership check. Any unauthenticated request with a known flow_id and file_name returns the image with HTTP 200. ### Details `src/backend/base/langflow/api/v1/files.py:138-164` — `download_image` takes `flow_id`: UUID as a bare path parameter with no Depends(get_flow) or `CurrentActiveUser`. All other file routes (`download_file`, `upload_file`, `list_files`, `delete_file`) use `Depends(get_flow)` which enforces both authentication and ownership. There is no global auth middleware on /api/v1; protection is per-endpoint only. ### PoC ``` curl -v "http://localhost:7860/api/v1/files/images/<flow_uuid>/<filename.png>" # Returns HTTP 200 with image bytes, no auth header required ``` ### Impact Unauthenticated cross-tenant data leak. In a multi-tenant deployment, any attacker who can discover or guess a `flow_id` (UUIDs can be leaked through other API responses) can download any user's uploaded images without credentials.

CVE-2026-33484 Affected Langflow Versions

1 component(s)
Fixed Versions:
1.9.0
Product / Package Ecosystem Affected Versions Fixed Version
langflow
pypi/langflow
PyPI
≥ 1.0.0
< 1.9.0
1.9.0

References

GitHub Advisory / Wiki ADVISORY
https://github.com/langflow-ai/langflow/security/advisories/GHSA-7grx-3xcx-2xv5
NVD — CVE-2026-33484 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-33484
Langflow Source Repository REPOSITORY
https://github.com/langflow-ai/langflow
Langflow Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/langflow/PYSEC-2026-80.yaml

Frequently Asked Questions

What is CVE-2026-33484?
CVE-2026-33484 is a security vulnerability in Langflow involving langflow has Unauthenticated IDOR on Image Downloads under CWE-284: Improper Access Control.
Which Langflow versions are affected?
Affected versions include releases prior to 1.9.0 across affected packages: langflow.
What version fixes CVE-2026-33484?
Upgrading to 1.9.0 (or the latest patched release for your respective branch) resolves the vulnerability.
Is langflow affected?
Yes, langflow is affected in releases prior to 1.9.0. Upgrade your dependency to 1.9.0 or later.
What is the CVSS score of CVE-2026-33484?
CVE-2026-33484 has a CVSS v3.1 base score of 7.5 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-33484?
CVE-2026-33484 is classified under CWE-284: Improper Access Control (The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.).
How can I check PyPI dependencies for CVE-2026-33484?
Run the dependency tree command: 'pip show langflow'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-7grx-3xcx-2xv5",
  "modified" : "2026-06-06T00:56:13Z",
  "published" : "2026-03-20T20:47:10Z",
  "aliases" : [ "CVE-2026-33484" ],
  "summary" : "langflow has Unauthenticated IDOR on Image Downloads",
  "details" : "### Summary\nThe `/api/v1/files/images/{flow_id}/{file_name}` endpoint serves image files without any authentication or ownership check. Any unauthenticated request with a known flow_id and file_name returns the image with HTTP 200.\n\n### Details\n`src/backend/base/langflow/api/v1/files.py:138-164` — `download_image` takes `flow_id`: UUID as a bare path parameter with no Depends(get_flow) or `CurrentActiveUser`. All other file routes (`download_file`, `upload_file`, `list_files`, `delete_file`) use `Depends(get_flow)` which enforces both authentication and ownership. There is no global auth middleware on /api/v1; protection is per-endpoint only.\n\n### PoC\n```\ncurl -v \"http://localhost:7860/api/v1/files/images/<flow_uuid>/<filename.png>\"\n# Returns HTTP 200 with image bytes, no auth header required\n```\n\n### Impact\nUnauthenticated cross-tenant data leak. In a multi-tenant deployment, any attacker who can discover or guess a `flow_id` (UUIDs can be leaked through other API responses) can download any user's uploaded images without credentials.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "langflow"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "1.0.0"
      }, {
        "fixed" : "1.9.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/langflow-ai/langflow/security/advisories/GHSA-7grx-3xcx-2xv5"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-33484"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/langflow-ai/langflow"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/langflow/PYSEC-2026-80.yaml"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-284", "CWE-639", "CWE-862" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-03-20T20:47:10Z",
    "nvd_published_at" : "2026-03-24T14:16:30Z"
  }
}