CVE-2026-55423
Langflow: Logout button does not clear session
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**.
How to fix CVE-2026-55423
To remediate CVE-2026-55423, upgrade the affected package to a fixed version below.
- —upgrade to 1.7.1 or later
Is CVE-2026-55423 being exploited?
No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-55423.
Affected packages (1)
- from 0, < 1.7.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM6.1 | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N |