MSRXCVE-2026-55255
CVE-2026-55255
Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow
Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
CVSS 3.1 · CNA
chance of exploitation in the next 30 days (EPSS; higher than 59% of CVEs)
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.
Scores
Affected packages and fixed versions
| Package | Ecosystem | Fixed in |
|---|---|---|
| langflow | PyPI | 1.9.1 |
Affected products
- langflow-ai langflow: < 1.9.1
Weakness: CWE-639
Also known as: GHSA-qrpv-q767-xqq2, PYSEC-2026-221
3 references (advisories, patches, write-ups)
- https://github.com/langflow-ai/langflow/security/advisories/GHSA-qrpv-q767-xqq2 · x_refsource_CONFIRM
- https://github.com/langflow-ai/langflow/pull/12832 · x_refsource_MISC
- https://github.com/langflow-ai/langflow/commit/2c9f498d664a3c32698b57d7c5e752625291060e · x_refsource_MISC
Sources: CVE.org, OSV.dev, FIRST EPSS. Missing ones did not answer or have no record yet.