CVE-2026-55255
Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow
At a glance
- Source
- NVD
- EPSS
- EPSS 0.89 % · percentile 59 ()
- State
- PUBLISHED
- Published
- Updated
- Assigner
- GitHub_M
- NVD status
- Analyzed
Description
Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.1, an Insecure Direct Object Reference (IDOR) vulnerability in /api/v1/responses endpoint allows an authenticated attacker to execute any flow belonging to another user by specifying the victim's flow ID in the request. This vulnerability is fixed in 1.9.1.
Weaknesses (CWE)
- CWE-639 — Authorization Bypass Through User-Controlled Key (IDOR)
References
- https://github.com/langflow-ai/langflow/security/advisories/GHSA-qrpv-q767-xqq2
- https://github.com/langflow-ai/langflow/pull/12832
- https://github.com/langflow-ai/langflow/commit/2c9f498d664a3c32698b57d7c5e752625291060e
- https://webflow.sysdig.com/blog/understanding-langflow-cve-2026-55255-and-why-higher-cvss-vulnerabilities-arent-always-the-most-exploited
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-55255
Scores
| Version | Score | Vector | Scored by |
|---|---|---|---|
| CVSS 3.1 | HIGH 8.4 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L | GitHub_M |
| CVSS 3.1 | HIGH 8.4 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L | NVD · security-advisories@github.com (Secondary) |
Advisories
- GHSA-qrpv-q767-xqq2 — Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow
- PYSEC-2026-221 — Langflow is a tool for building and deploying AI-powered agents and workflows. Prior to 1.9.2, an Insecure Direct Object Reference (IDOR) vulnerability in /api/
European references
- ENISA EUVD · EUVD-2026-38517
- GCVE · GCVE-0-2026-55255
Affected configurations (NVD CPE)
cpe:2.3:a:langflow:langflow:*:*:*:*:*:*:*:*< 1.9.1
Affected products
| Product | Versions |
|---|---|
| langflow-ai · langflow | affected < 1.9.1 |
Sources
| Source | Licence |
|---|---|
| CVE List (CVEProject cvelistV5) | CVE Program Terms of Use |
| CISA Known Exploited Vulnerabilities | CC0 1.0 |
| EPSS (FIRST.org) | FIRST — attribution requested |
| ENISA EUVD | ENISA — reproduction authorised, source acknowledged |
| NVD (NIST) via fkie-cad/nvd-json-data-feeds | Public domain — this product uses data from the NVD API but is not endorsed or certified by the NVD |