Fortimail
CVE-2021-24020
CRITICAL
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A04:2025 - Cryptographic Failures
ASVS 5.0
V11 - Cryptography Signature verification
|
| Impact | CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. |
| Exploit ScenarioDerived | This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system. |
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Alert meAnalysisAI
A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.
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Technical ContextAI · show details
This vulnerability is classified under CWE-347. A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification. Affected products include: Fortinet Fortimail. Version information: through 6.4.4.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.
Threat Intelligence Overview
NVD
CVE.org
EPSS
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Authentication bypass attacks exploit flaws in the verification mechanisms that control access to systems and applications.
Affected Products (CPE)NVD
Unauthenticated path traversal in Fortinet FortiMail (7.2.0-7.2.9, 7.4.0-7.4.8, 7.6.0-7.6.6 and 8.0.0-8.0.1) lets a remo
An improper authentication vulnerability in FortiMail 5.4.10, 6.0.7, 6.2.2 and earlier and FortiVoiceEntreprise 6.0.0 an
An improper access control vulnerability in FortiMail version 7.4.0 configured with RADIUS authentication and remote_wil
Multiple improper neutralization of special elements of SQL commands vulnerabilities in FortiMail before 6.4.4 may allow
Multiple cross-site scripting (XSS) vulnerabilities in admin/FEAdmin.html in Fortinet FortiMail before 4.3.4 on FortiMai
Authenticated SQL injection in Fortinet FortiMail versions 7.6.0 through 7.6.3, 7.4.0 through 7.4.5, and 7.2.0 through 7
An incorrect authorization vulnerability [CWE-863] in FortiMail webmail version 7.2.0 through 7.2.2, version 7.0.0 throu
The combination of various cryptographic issues in the session management of FortiMail 6.4.0 through 6.4.4 and 6.2.0 thr
An improper neutralization of special elements used in an OS Command vulnerability in the administrative interface of Fo
Multiple instances of incorrect calculation of buffer size in the Webmail and Administrative interface of FortiMail befo
An insufficient verification of data authenticity vulnerability [CWE-345] in FortiClient, FortiMail and FortiOS AV engin
Cross-site scripting (XSS) vulnerability in the Web Action Quarantine Release feature in the WebGUI in Fortinet FortiMai
GitHub PoC
Exploit-DB