CVE-2026-55255 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-55255HIGH

langflow-ai langflow — Langflow: IDOR Vulnerability in `/api/v1/responses` Endpoint Allows Authenticated Attackers to Access Another User's Flow

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   H   L   N  C  H  H  L    8.4   .2905   98.0   YES

AFFECTED
  Product   Versions   Fixed
  langflow  < 1.9.1 –  —

TIMELINE
  Jun 16  Reserved by GitHub_M
  Jul 7   EXPLOIT PUBLISHED — CVE-2026-55255 (langflow-ai langflow). Public exploit reference added.
  Jul 7   Added to CISA KEV, remediation due 2026-07-10
  Jul 7   Published (CNA: GitHub_M)
  Jul 11  DUE DATE PASSED — CVE-2026-55255 (langflow-ai langflow). CISA remediation deadline was July 10, 2026; still in catalog.

CWE-639 · CNA: GitHub_M · CVSS v3.1 · 5 references · NVD status: Analyzed · KEV due July 10, 2026

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.

Lifecycle

Complete event history — 5 events, chronological
Date	Event	Detail
June 16, 2026	Reserved	Reserved by GitHub_M
July 7, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-55255 (langflow-ai langflow). Public exploit reference added.
July 7, 2026	KEV ADDED	Added to CISA KEV, remediation due 2026-07-10
July 7, 2026	Published	Published (CNA: GitHub_M)
July 11, 2026	DUE DATE PASSED	DUE DATE PASSED — CVE-2026-55255 (langflow-ai langflow). CISA remediation deadline was July 10, 2026; still in catalog.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
langflow-ai	langflow	—	< 1.9.1	—

Weaknesses

CWE-639

References (5)

https://github.com/langflow-ai/langflow/commit/2c9f498d664a3c32698b57d7c5e752625291060e [Patch]
https://github.com/langflow-ai/langflow/pull/12832 [Issue Tracking, Patch]
https://github.com/langflow-ai/langflow/security/advisories/GHSA-qrpv-q767-xqq2 [Exploit, Mitigation, Vendor Advisory]
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]

Authoritative record: CVE-2026-55255 at cve.org

Vendors: langflow-ai

Weaknesses: CWE-639

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-55255 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.