Langflow: Logout button does not clear session

Answer in brief

CVE-2026-55423 records a Medium severity (CVSS 6.1) vulnerability in Langflow: Logout button does not clear session. The current sources do not mark it as known exploited. The current feed maps langflow (pip), langflow (pypi). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jun 19, 2026Updated Sep 24, 2026Source checked Sep 25, 2026First seen by HOL Jun 19, 2026Material review Sep 24, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.1
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 6.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps langflow (pip), langflow (pypi). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
langflowpip	<1.7.0	1.7.1, 1.7.0
langflowpypi	>=0 <1.7.0	1.7.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for langflow, langflow.
Review the reported fix. Update langflow to 1.7.1; langflow to 1.7.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jun 19, 2026
Evidence: source:ghsa:source_dates:source-dates:record
Source modified
Sep 24, 2026
Evidence: source:ghsa:source_dates:source-dates:record
First seen by HOL
Jun 19, 2026

Sources and claim methodology

Upstream source 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**.

Quoted source text, attributed separately from HOL analysis.