High 8.4Known exploited (CISA KEV)Published Jun 23, 2026

CVE-2026-55255Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow

Updated under an hour ago (Oct 26, 2026, 1:40 PM ET)

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It affects langflow-ai langflow and 1 other product. Add what you run to find out whether that includes you.

CISA lists it as known exploited since Jul 7, 2026; federal agencies had to remediate by Jul 10, 2026. Treat that date as your deadline.

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Every CVE for langflow-ai langflow

Exploited in the last 30 days

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.

CVSS: 8.4 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:L
Weakness (CWE): CWE-639
Known exploited: Added to CISA KEV Jul 7, 2026; federal remediation due Jul 10, 2026Apply 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.
EPSS (exploitation in the next 30 days): 0.89% (percentile 59)
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Oct 7, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

langflow-ai langflow langflow_ai:langflow (from the name)	before 1.9.1	CNA record
langflow langflow langflow:langflow	before 1.9.1	NVD

References

References

https://github.com/langflow-ai/langflow/security/advisories/GHSA-qrpv-q767-xqq2	x-refsource-confirm, exploit, mitigation, vendor-advisory
https://github.com/langflow-ai/langflow/pull/12832	x-refsource-misc, issue-tracking, patch
https://github.com/langflow-ai/langflow/commit/2c9f498d664a3c32698b57d7c5e752625291060e	x-refsource-misc, patch
https://webflow.sysdig.com/blog/understanding-langflow-cve-2026-55255-and-why-higher-cvss-vulnerabilities-arent-always-the-most-exploited	third-party-advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-55255	us-government-resource

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.