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Langflow: Logout button does not clear session

Moderate severity GitHub Reviewed Published Jun 19, 2026 in langflow-ai/langflow • Updated Jun 19, 2026

Package

pip langflow (pip)

Affected versions

< 1.7.0

Patched versions

1.7.1

Description

Summary

The logout button does not clear the session. The previous user stays logged in unless another user explicitly logs in.

Details

Not in auto login mode. Hosted on localhost. access_token_lf remains present in both Local Storage and Cookies. refresh_token_lf remains present in Cookies.

Root cause: the /logout endpoint deleted the authentication cookies without matching the original httponly/samesite/secure/domain parameters, so the browser kept them; additionally the frontend did not clear the auth cookies on logout.

LANGFLOW_AUTO_LOGIN: "False"
LANGFLOW_SUPERUSER: <set>
LANGFLOW_SUPERUSER_PASSWORD: <set>
LANGFLOW_SECRET_KEY: <set>
LANGFLOW_NEW_USER_IS_ACTIVE: "False"
LANGFLOW_ENABLE_SUPERUSER_CLI: "False"

PoC

Click Logout. Hit refresh to return to previous screen.

Impact

Users on shared computers may falsely believe they have terminated their session.

Patches

Fixed in 1.7.0 (PRs #10527 and #10528). The logout endpoint now deletes the auth cookies using the same parameters they were created with, and the frontend clears the auth cookies on logout. Upgrade to 1.7.0 or later.

References

@AntonioABLima AntonioABLima published to langflow-ai/langflow Jun 19, 2026
Published to the GitHub Advisory Database Jun 19, 2026
Reviewed Jun 19, 2026
Last updated Jun 19, 2026

Severity

Moderate

CVSS overall score

This score calculates overall vulnerability severity from 0 to 10 and is based on the Common Vulnerability Scoring System (CVSS).
/ 10

CVSS v3 base metrics

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

CVSS v3 base metrics

Attack vector: More severe the more the remote (logically and physically) an attacker can be in order to exploit the vulnerability.
Attack complexity: More severe for the least complex attacks.
Privileges required: More severe if no privileges are required.
User interaction: More severe when no user interaction is required.
Scope: More severe when a scope change occurs, e.g. one vulnerable component impacts resources in components beyond its security scope.
Confidentiality: More severe when loss of data confidentiality is highest, measuring the level of data access available to an unauthorized user.
Integrity: More severe when loss of data integrity is the highest, measuring the consequence of data modification possible by an unauthorized user.
Availability: More severe when the loss of impacted component availability is highest.
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS score

Exploit Prediction Scoring System (EPSS)

This score estimates the probability of this vulnerability being exploited within the next 30 days. Data provided by FIRST.
(5th percentile)

Weaknesses

Insufficient Session Expiration

According to WASC, Insufficient Session Expiration is when a web site permits an attacker to reuse old session credentials or session IDs for authorization. Learn more on MITRE.

CVE ID

CVE-2026-55423

GHSA ID

GHSA-7hw8-6q6r-4276

Source code

Credits

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