CVE-2026-33309CRITICAL 9.9EPSS p69.3%
CVE-2026-33309CVE-2026-33309
Description
Langflow is a tool for building and deploying AI-powered agents and workflows. Versions 1.2.0 through 1.8.1 have a bypass of the patch for CVE-2025-68478 (External Control of File Name), leading to the root architectural issue within `LocalStorageService` remaining unresolved. Because the underlying storage layer lacks boundary containment checks, the system relies entirely on the HTTP-layer `ValidatedFileName` dependency. This defense-in-depth failure leaves the `POST /api/v2/files/` endpoint vulnerable to Arbitrary File Write. The multipart upload filename bypasses the path-parameter guard, allowing authenticated attackers to write files anywhere on the host system, leading to Remote Code Execution (RCE). Version 1.9.0 contains an updated fix.
Scoring
| CVSS 3.1 | 9.9 (CRITICAL) |
| Vector | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H |
| EPSS | 1.42% probability of exploitation · percentile 69.3% · 2026-06-19T12:03:05Z |
| Published | 2026-03-24 |
| Last modified | 2026-03-24 |
Underlying weaknesses· 4
References
4
| Type | Target | Confidence | Tier |
|---|---|---|---|
| Weakness | Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')cwe-22 | 0% | live |
| Weakness | Improper Access Controlcwe-284 | 0% | live |
| Weakness | External Control of File Name or Pathcwe-73 | 0% | live |
| Weakness | Improper Control of Generation of Code ('Code Injection')cwe-94 | 0% | live |
Related by meaning· 6
Nearest entities by semantic similarity across the cs-graph corpus.