CVE-2026-104286

CRITICAL

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.

CVSS v3.1 Score

9.8
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Published: 10/1/2026Modified: 10/2/2026

Related Intelligence (4)

CRITICALZero Day

Exploited Fortinet FortiMail Zero-Day Calls for Urgent Action

CVE-2026-104286 is a critical-severity path traversal vulnerability that could allow attackers to write arbitrary files to the system. The post Exploited Fortinet FortiMail Zero-Day Calls for Urgent Action appeared first on SecurityWeek .

CVE-2026-104286
SecurityWeek
CRITICALZero Day

Critical FortiMail Zero-Day Flaw Exploited in Attacks Allows Unauthenticated Arbitrary File Writes

The U.S. Cybersecurity and Infrastructure Security Agency (CISA), on Thursday, added a critical security flaw impacting Fortinet FortiMail to its Known Exploited Vulnerabilities (KEV) catalog, following reports of active exploitation. The vulnerability, tracked as CVE-2026-104286 (CVSS score: 9.8), allows unauthenticated attackers to write arbitrary files on the underlying system. "An improper

CVE-2026-104286
The Hacker News
CRITICALZero Day

Fortinet warns of critical FortiMail flaw exploited in zero-day attacks

Fortinet is warning customers of a critical FortiMail vulnerability, tracked as CVE-2026-104286, that is being actively exploited in zero-day attacks to execute unauthorized code or commands on vulnerable devices. [...]

CVE-2026-104286
BleepingComputer
HIGHVulnerability

CISA KEV: Fortinet FortiMail — Fortinet FortiMail Path Traversal Vulnerability

Fortinet FortiMail contains a path traversal and an improper neutralization of NULL byte or NULL character vulnerability that may allow an unauthenticated attacker to write arbitrary files on the underlying system via crafted HTTP or HTTPS requests.

CVE-2026-104286Fortinet FortiMail
CISA KEV

References (2)

https://fortiguard.fortinet.com/psirt/FG-IR-26-175MitigationVendor Advisoryhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-104286US Government Resource