---
id: "CVE-2024-55591"
kind: "vulnerability"
aliases: ["CVE-2024-55591"]
title: "An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] affecting FortiOS version 7.0.0\u2026"
severity: "critical"
cvss: 9.8
epss: null
exploited: true
status: "open"
category: "infrastructure"
products: [{"name": "Fortinet FortiOS and FortiProxy", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "fortinet fortiproxy", "fixed": ["7.0.20"], "affected": ">= 7.0.0, < 7.0.20", "ecosystem": "vendor"}, {"name": "fortinet fortiproxy", "fixed": ["7.2.13"], "affected": ">= 7.2.0, < 7.2.13", "ecosystem": "vendor"}, {"name": "fortinet fortios", "fixed": ["7.0.17"], "affected": ">= 7.0.0, < 7.0.17", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["exploited", "firewall", "fortinet", "fortios", "fortiproxy", "infrastructure", "ransomware", "vpn"]
not_affected_if: ["unknown"]
published_at: "2025-01-14T00:00:00+00:00"
first_seen_at: "2026-10-23T19:11:51+00:00"
updated_at: "2026-10-23T22:29:05+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2024-55591", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-55591", "first_seen_at": "2026-10-23T22:29:05+00:00"}]
---

# An Authentication Bypass Using an Alternate Path or Channel vulnerability [CWE-288] affecting FortiOS version 7.0.0…

Fortinet FortiOS and FortiProxy contain an authentication bypass in the Node.js websocket module that lets an unauthenticated remote attacker gain super-admin privileges. CISA lists it as exploited in the wild and tied to ransomware campaigns.

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

## Affected

- vendor:Fortinet FortiOS and FortiProxy affected ? fixed ?
- vendor:fortinet fortiproxy affected >= 7.0.0, < 7.0.20 fixed 7.0.20
- vendor:fortinet fortiproxy affected >= 7.2.0, < 7.2.13 fixed 7.2.13
- vendor:fortinet fortios affected >= 7.0.0, < 7.0.17 fixed 7.0.17

## Fix

Apply the vendor mitigations per Fortinet's advisory; the sources do not name fixed versions. If no mitigation is available, discontinue use of the product per CISA.

## Timeline

- 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2024-55591
- 2026-10-23T22:29:05+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2024-55591

## From the sources

Fortinet FortiOS and FortiProxy contain an authentication bypass vulnerability that may allow an unauthenticated, remote attacker to gain super-admin privileges via crafted requests to Node.js websocket module.

CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

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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_