CVE-2026-126151

Authentication Algorithm Vulnerability Allowing Unauthenticated Remote Account Takeover

Published Nov 11, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed

Description

A incorrect implementation of authentication algorithm 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 an unauthenticated remote attacker to gain elevation of privilege (account takeover) via a crafted request.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

Fortinet

FortiMail

unaffected

Version	Status	Constraints
`8.0.0`	affected	≤ 8.0.1
`7.6.0`	affected	≤ 7.6.6
`7.4.0`	affected	≤ 7.4.8
`7.2.0`	affected	≤ 7.2.9

No data.

Vendor Product Versions

Fortinet

Fortimail

Version	Status	Scheme	Platform
`[8.0.0,8.0.1]`	affected	semver	—
`[7.6.0,7.6.6]`	affected	semver	—
`[7.4.0,7.4.8]`	affected	semver	—
`[7.2.0,7.2.9]`	affected	semver	—

Remediation

Vendor Solution

Upgrade to FortiMail version 8.0.2 or above Upgrade to FortiMail version 7.6.7 or above Upgrade to FortiMail version 7.4.9 or above

Tracking

Advisories

No advisories available

Metrics

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.584% probability within 30 days)

Key SSVC decision points have not yet been added.

References

Link	Providers
https://fortiguard.fortinet.com/psirt/FG-IR-26-203

History

Nov 12, 2026 4:15 PM Title updated View changes

Type	Values Removed	Values Added
Title		Authentication Algorithm Vulnerability Allowing Unauthenticated Remote Account Takeover

Nov 11, 2026 9:45 PM Description updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		A incorrect implementation of authentication algorithm 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 an unauthenticated remote attacker to gain elevation of privilege (account takeover) via a crafted request.
First Time appeared		Fortinet Fortinet fortimail
Weaknesses		CWE-303
CPEs		cpe:2.3:a:fortinet:fortimail:7.2.0:::::::* cpe:2.3:a:fortinet:fortimail:7.2.1:::::::* cpe:2.3:a:fortinet:fortimail:7.2.2:::::::* cpe:2.3:a:fortinet:fortimail:7.2.3:::::::* cpe:2.3:a:fortinet:fortimail:7.2.4:::::::* cpe:2.3:a:fortinet:fortimail:7.2.5:::::::* cpe:2.3:a:fortinet:fortimail:7.2.6:::::::* cpe:2.3:a:fortinet:fortimail:7.2.7:::::::* cpe:2.3:a:fortinet:fortimail:7.2.8:::::::* cpe:2.3:a:fortinet:fortimail:7.2.9:::::::* cpe:2.3:a:fortinet:fortimail:7.4.0:::::::* cpe:2.3:a:fortinet:fortimail:7.4.1:::::::* cpe:2.3:a:fortinet:fortimail:7.4.2:::::::* cpe:2.3:a:fortinet:fortimail:7.4.3:::::::* cpe:2.3:a:fortinet:fortimail:7.4.4:::::::* cpe:2.3:a:fortinet:fortimail:7.4.5:::::::* cpe:2.3:a:fortinet:fortimail:7.4.6:::::::* cpe:2.3:a:fortinet:fortimail:7.4.7:::::::* cpe:2.3:a:fortinet:fortimail:7.4.8:::::::* cpe:2.3:a:fortinet:fortimail:7.6.0:::::::* cpe:2.3:a:fortinet:fortimail:7.6.1:::::::* cpe:2.3:a:fortinet:fortimail:7.6.2:::::::* cpe:2.3:a:fortinet:fortimail:7.6.3:::::::* cpe:2.3:a:fortinet:fortimail:7.6.4:::::::* cpe:2.3:a:fortinet:fortimail:7.6.5:::::::* cpe:2.3:a:fortinet:fortimail:7.6.6:::::::* cpe:2.3:a:fortinet:fortimail:8.0.0:::::::* cpe:2.3:a:fortinet:fortimail:8.0.1:::::::*
Vendors & Products		Fortinet Fortinet fortimail
References		https://fortiguard.fortinet.com/psirt/FG-IR-26-203
Metrics		cvssV3_1 `{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:R'}`