CVE-2026-6542
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIBM Langflow OSS 1.0.0 through 1.8.4 could allow any user to supply a flow_id to read transaction logs and vertex build data belonging to other users, and to delete persisted vertex build data for another user's flow.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceIBM Langflow OSS versions 1.0.0 through 1.8.4 contain an Insecure Direct Object Reference (IDOR) vulnerability where the application fails to validate ownership of flow_id parameters before allowing read or delete operations. Any authenticated user can read transaction logs and vertex build data from other users' flows, and can delete persisted vertex build data belonging to other users by supplying their flow_id.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data>= 1.0.0, < 1.9.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Determine installed Langflow versionCheck the installed package version using pip show langflow, check the running container tag, or inspect the version file in the installation directoryAffected if The installed version is >= 1.0.0 and < 1.9.0
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Verify authentication is enabledCheck the Langflow configuration files or environment variables for authentication settings such as LANGFLOW_AUTH_ENABLED, and confirm users are required to log in to access the applicationAffected if Authentication is disabled or optional, allowing unauthenticated access to the API
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Confirm API endpoints are exposedInspect network exposure of the Langflow API service (typically port 7860 or 8080) and verify the /api/v1/flows endpoint is accessible over the networkAffected if The flow API endpoints are network-accessible without additional access controls
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Check for access control configurationReview the Langflow configuration for any authorization or access control settings related to flow ownership validationAffected if No ownership validation middleware is configured or the application relies solely on user authentication without verifying flow ownership
A user is affected if Langflow version is 1.0.0 through 1.8.4 inclusive and authentication is enabled, since any authenticated user can access or modify other users' flow data via the vulnerable flow_id parameter.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped1.9.0
Implement proper authorization checks to verify the authenticated user owns the flow_id before permitting read or delete operations on flow data. Consider adding ownership validation middleware and audit logging for sensitive data access.
1.9.0 or later
- 1. Backup your current Langflow data and configuration files
- 2. Verify your current Langflow version by checking the installed package or running `langflow --version`
- 3. Stop the Langflow service
- 4. Upgrade Langflow to version 1.9.0 or later using your package manager (e.g., `pip install langflow>=1.9.0` or `pip install --upgrade langflow`)
- 5. Verify the upgrade was successful by checking the new version
- 6. Start the Langflow service
- 7. Test that the IDOR vulnerability is mitigated by confirming users can no longer access other users' flow data using arbitrary flow_id values
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation6.0 h
- Testing3.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-6542 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-6542 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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