---
id: "CVE-2026-126154"
page: "https://infrastack.ai/live/CVE-2026-126154"
kind: "vulnerability"
aliases: ["CVE-2026-126154"]
title: "Fortinet FortiMail: crafted HTTP request can crash the mail appliance"
severity: "high"
cvss: 7.5
epss: null
exploited: false
status: "open"
category: "vendor"
products: [{"name": "FortiMail", "fixed": ["8.0.2", "7.6.7", "7.4.9"], "affected": ">= 8.0.0, <= 8.0.1; >= 7.6.0, <= 7.6.6; >= 7.4.0, <= 7.4.8; 7.2 all versions", "ecosystem": "vendor"}]
ecosystems: []
tags: ["email-gateway", "fortimail", "fortinet", "self-hosted", "vendor"]
not_affected_if: ["fortimail-cloud", "managed-hosting", "other-fortimail-versions"]
published_at: "2026-11-11T22:17:13+00:00"
first_seen_at: "2026-11-11T22:29:28+00:00"
updated_at: "2026-11-11T22:48:46+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-126154", "first_seen_at": "2026-11-11T22:29:28+00:00"}, {"source": "analyst", "url": "https://fortiguard.fortinet.com/psirt/FG-IR-26-206", "first_seen_at": "2026-11-11T22:48:46+00:00", "cites": ["https://fortiguard.fortinet.com/psirt/FG-IR-26-206", "https://nvd.nist.gov/vuln/detail/CVE-2026-126154"]}]
exploit_sources: []
---

# Fortinet FortiMail: crafted HTTP request can crash the mail appliance

Link for people: https://infrastack.ai/live/CVE-2026-126154 (this .md is for agents)

An out-of-bounds write in several FortiMail releases lets a remote, unauthenticated attacker send a specially crafted HTTP request. The result is a denial of service, meaning the mail appliance stops working.

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

## Affected

- vendor:FortiMail affected >= 8.0.0, <= 8.0.1; >= 7.6.0, <= 7.6.6; >= 7.4.0, <= 7.4.8; 7.2 all versions fixed 8.0.2, 7.6.7, 7.4.9

## How to check

- Check the FortiMail version under the admin dashboard or with `get system status` in the CLI.
- Compare the version against the affected ranges: 8.0.0 through 8.0.1, 7.6.0 through 7.6.6, 7.4.0 through 7.4.8, and all 7.2 releases.

## Fix

Upgrade FortiMail 8.0.x to 8.0.2 or above, 7.6.x to 7.6.7 or above, 7.4.x to 7.4.9 or above. FortiMail 7.2 (all versions) has no fix in its branch: migrate to a fixed release.

## Timeline

- 2026-11-11T22:29:28+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-126154
- 2026-11-11T22:48:46+00:00 analyst https://fortiguard.fortinet.com/psirt/FG-IR-26-206 — Read Fortinet FG-IR-26-206 (published 2026-11-10): affected and fixed versions confirmed; FortiMail Cloud already patched Oct 05 2026; no workaround or virtual patch listed. Exploitation status not read on the page, left false.

## Documents

- [advisory] FG-IR-26-206 Out-of-bounds write (FortiMail) https://fortiguard.fortinet.com/psirt/FG-IR-26-206
- [describes] NVD CVE-2026-126154 https://nvd.nist.gov/vuln/detail/CVE-2026-126154

## From the sources

A out-of-bounds write vulnerability in Fortinet FortiMail 8.0.0 through 8.0.1, FortiMail 7.6.0 through 7.6.6, FortiMail 7.4.0 through 7.4.8, FortiMail 7.2 all versions may allow a remote unauthenticated attacker to cause a denial of service via a specially crafted HTTP request.

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_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_