---
id: "CVE-2021-40870"
kind: "vulnerability"
aliases: ["CVE-2021-40870"]
title: "Aviatrix Aviatrix Controller: Aviatrix Controller Unrestricted Upload of File"
severity: "critical"
cvss: 9.8
epss: 0.93019
exploited: true
status: "open"
category: "vendor"
products: [{"name": "Aviatrix Aviatrix Controller", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["aviatrix", "cloud-networking", "exploited", "self-hosted", "vendor"]
not_affected_if: ["managed-hosting"]
published_at: "2021-09-13T08:15:13+00:00"
first_seen_at: "2026-10-23T19:11:53+00:00"
updated_at: "2026-10-23T21:57:35+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-40870", "first_seen_at": "2026-10-23T19:11:53+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2021-40870", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-40870", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Aviatrix Aviatrix Controller: Aviatrix Controller Unrestricted Upload of File

Aviatrix Controller accepts file uploads of dangerous types without restriction, and a directory traversal in the upload path lets an unauthenticated attacker write files anywhere. The sources say this leads to arbitrary code execution, and CISA lists it as actively exploited.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Aviatrix Aviatrix Controller affected ? fixed ?

## Fix

Apply the vendor update per Aviatrix instructions; the fixed version is unknown from the sources.

## Timeline

- 2026-10-23T19:11:53+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-40870
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2021-40870
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2021-40870

## From the sources

An issue was discovered in Aviatrix Controller 6.x before 6.5-1804.1922. Unrestricted upload of a file with a dangerous type is possible, which allows an unauthenticated user to execute arbitrary code via directory traversal.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_