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CVE-2026-126157 fortinet fortimail: Improper Authentication

9.1 criticalEPSS 0.4%

Critical (9.1) in fortinet fortimail. EPSS 0.4% estimated probability of exploitation activity in the next 30 days.

On this page
A improper authentication 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 attacker to gain access to other users' secure email accounts via crafted HTTP requests.

Severity

CVSS 3.1

9.1 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS
0.4% estimated probability of exploitation activity in the next 30 days; 36th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-287 Improper Authentication
OWASP Top 10
A07:2025 Authentication Failures
Published
Modified
Assigned by
fortinet (CNA)
NVD analysis
Awaiting analysis
Record from
the NVD, synced

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Affected

Versions

From the CNA's record in the CVE List.

ProductAffected
Fortinet FortiMailfrom 8.0.0 through 8.0.1
Fortinet FortiMailfrom 7.6.0 through 7.6.6
Fortinet FortiMailfrom 7.4.0 through 7.4.8
Fortinet FortiMailfrom 7.2.0 through 7.2.9
Fortinet FortiMailfrom 7.0.0 through 7.0.9

Attack patterns (CAPEC)

  • CAPEC-22 Exploiting Trust in Client Likelihood: High · Severity: High
  • CAPEC-57 Utilizing REST's Trust in the System Resource to Obtain Sensitive Data Likelihood: Medium · Severity: Very High
  • CAPEC-94 Adversary in the Middle (AiTM) Likelihood: High · Severity: Very High
  • CAPEC-114 Authentication Abuse Severity: Medium
  • CAPEC-115 Authentication Bypass Severity: Medium
  • CAPEC-151 Identity Spoofing Likelihood: Medium · Severity: Medium
  • CAPEC-194 Fake the Source of Data Severity: Medium
  • CAPEC-593 Session Hijacking Likelihood: High · Severity: Very High
  • CAPEC-633 Token Impersonation Severity: Medium
  • CAPEC-650 Upload a Web Shell to a Web Server Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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