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GHSA-rf6x-r45m-xv3w CVE-2026-33053 PYSEC-2026-78

Langflow is Missing Ownership Verification in API Key Deletion (IDOR)

High PyPI
Severity
0.0 / 10
High · CVSS 4.0
Exploit chance (EPSS)
0.40%
Chance of exploitation in the next 30 days. Higher than 34.77% of scored vulnerabilities.
Known exploited
No
Not in CISA's catalog
Weakness
CWE-639 Authorization Bypass Through User-Controlled Key
Fix
1.9.0
Upgrade langflow to this version or later

Description

Detection Method: Kolega.dev Deep Code Scan

Attribute Value
Location src/backend/base/langflow/api/v1/api_key.py:44-53
Practical Exploitability High
Developer Approver faizan@kolega.ai

Description

The delete_api_key_route() endpoint accepts an api_key_id path parameter and deletes it with only a generic authentication check (get_current_active_user dependency). However, the delete_api_key() CRUD function does NOT verify that the API key belongs to the current user before deletion.

Affected Code

@router.delete("/{api_key_id}", dependencies=[Depends(auth_utils.get_current_active_user)])
async def delete_api_key_route(
    api_key_id: UUID,
    db: DbSession,
):
    try:
        await delete_api_key(db, api_key_id)
    except Exception as e:
        raise HTTPException(status_code=400, detail=str(e)) from e
    return {"detail": "API Key deleted"}

Evidence

In crud.py lines 44-49, delete_api_key() retrieves the API key by ID and deletes it without checking if the key belongs to the authenticated user. The endpoint also doesn't pass the current_user to the delete function for verification.

Impact

An authenticated attacker can enumerate and delete API keys belonging to other users by guessing or discovering their API key IDs. This allows account takeover, denial of service, and disruption of other users' integrations.

Recommendation

Modify the delete_api_key endpoint and function: (1) Pass current_user to the delete function; (2) In delete_api_key(), verify api_key.user_id == current_user.id before deletion; (3) Raise a 403 Forbidden error if the user doesn't own the key. Example: if api_key.user_id != user_id: raise HTTPException(status_code=403, detail='Unauthorized')

Notes

Confirmed IDOR vulnerability. The delete_api_key_route endpoint at line 44-53 accepts an api_key_id and calls delete_api_key(db, api_key_id) without passing the current_user. The CRUD function delete_api_key() at crud.py:44-49 retrieves the API key by ID and deletes it without verifying ownership (api_key.user_id == current_user.id). Compare this to the GET endpoint at lines 17-28 which correctly filters by user_id, and the POST endpoint at lines 31-41 which correctly associates the key with user_id. An authenticated attacker can delete any user's API keys by guessing/enumerating UUIDs. Fix: Pass current_user to delete_api_key and verify api_key.user_id == current_user.id before deletion, returning 403 if unauthorized.

Developer Review Notes

Does not accept current_user as a parameter. Allowing deletion of any user's API keys even without permissions.

Affected versions

PyPI

PackageVulnerableFixed in
langflow
< 1.9.0
1.9.0

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

langflow PyPI → 1.9.0

pip
pip install --upgrade "langflow>=1.9.0"
poetry
poetry add "langflow>=1.9.0"
uv
uv add "langflow>=1.9.0"

Severity breakdown

CVSS 4.0 0.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Attack vector
Network
Attack complexity
Low
Attack requirements
None
Privileges required
Low
User interaction
None
Confidentiality (vulnerable system)
None
Integrity (vulnerable system)
None
Availability (vulnerable system)
High
Confidentiality (subsequent systems)
None
Integrity (subsequent systems)
None
Availability (subsequent systems)
None

CVSS 3.1 8.8

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

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Weakness

CWE-639: Authorization Bypass Through User-Controlled Key

The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.

How to prevent it
  • Architecture and Design: For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
  • Architecture and Design, Implementation: Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
  • Architecture and Design: Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.

References

Timeline

  1. Published
  2. Last updated by the source
  3. Latest EPSS score
AdvisorySeverityWhy it's related
GHSA-qrpv-q767-xqq2
Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow
High Known exploited Also affects langflow
GHSA-vwmf-pq79-vjvx
Unauthenticated Remote Code Execution in Langflow via Public Flow Build Endpoint
Critical Known exploited Also affects langflow
GHSA-g22f-v6f7-2hrh
Langflow affected by Remote Code Execution via validate_code() exec()
High Known exploited Also affects langflow
GHSA-577h-p2hh-v4mv
Langflow CORS misconfiguration enables Account Takeover and RCE
Critical Known exploited Also affects langflow
GHSA-rvqx-wpfh-mfx7
Langflow Unauth RCE
Critical Known exploited Also affects langflow
GHSA-j8f7-x8jm-wmm4
Langflow: SSRF in URL-taking components (protection disabled by default / warn-only, not applied to RSS, SearXNG, Web Search, Home Assistant, Glean, Docling)
Medium Also affects langflow
GHSA-4f6c-2vvp-gw82
Langflow: IP Spoofing Bypass via `X-Forwarded-For` Allowing Remote Configuration Write
High Also affects langflow
GHSA-4hmc-cfm3-w43c
Langflow has Authenticated Cross-Project File Disclosure via Unscoped MCP Resource Handlers
High Also affects langflow
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