CVE-2026-104286

critical

Description

An improper limitation of a pathname to a restricted directory ('path traversal') 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 7.2.0 through 7.2.9 may allow an unauthenticated attacker to write arbitrary files on the underlying system via crafted HTTP or HTTPS requests.

https://www.theregister.com/security/2026/10/02/fortinet-sounds-the-alarm-over-actively-exploited-fortimail-zero-day/5300803

https://www.securityweek.com/exploited-fortinet-fortimail-zero-day-calls-for-urgent-action/

https://www.helpnetsecurity.com/2026/10/02/fortinet-fortimail-vulnerability-cve-2026-104286/

https://securityaffairs.com/200224/security/u-s-cisa-adds-fortinet-fortimail-flaw-to-its-known-exploited-vulnerabilities-catalog.html

https://www.cisa.gov/news-events/alerts/2026/10/01/cisa-adds-one-known-exploited-vulnerability-catalog

https://www.bleepingcomputer.com/news/security/fortinet-warns-of-critical-fortimail-flaw-exploited-in-zero-day-attacks/

https://thehackernews.com/2026/10/critical-fortimail-zero-day-flaw.html

https://github.com/completetech-security/fortimail-cve-2026-104286-check

https://github.com/CompleTetech-Security/fortimail-cve-2026-104286-check

https://github.com/Blueangelman36/cve-notifier

https://github.com/kh20134/fortimail-cve-2026-104286-response

https://github.com/techupdate24/fortimail-zero-day-cve-2026-104286

https://github.com/ShadowForge-Cyber/CVE-2026-104286-POC

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-104286

https://fortiguard.fortinet.com/psirt/FG-IR-26-175

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-91042

Details

Source: Mitre, NVD

Published: 2026-10-01

Updated: 2026-10-07

Known Exploited Vulnerability (KEV)

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 9.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

EPSS

EPSS: 0.04573

Vulnerability Watch

Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.

Vulnerability of Interest

Detections

Analytics