CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N
Lifecycle Timeline
2DescriptionNVD
MDaemon Mail Server 23.5.2 validates SPF, DKIM, and DMARC using the email enclosed in angle brackets (<>) in the From: header of SMTP DATA. An attacker can craft a From: header with multiple invisible Unicode thin spaces to display a spoofed sender while passing validation, allowing email spoofing even when anti-spoofing protections are in place. NOTE: this is disputed by the Supplier because UI spoofing occurs in a client, not in a server such as MDaemon's product or any other server implementation. Also, if a client without its own spoofing protection must be used, the Header Screening feature in MDaemon's product can be employed to mitigate the client-side vulnerability.
AnalysisAI
MDaemon Mail Server 23.5.2 validates SPF, DKIM, and DMARC using the email enclosed in angle brackets (<>) in the From: header of SMTP DATA. Rated high severity (CVSS 7.1), this vulnerability is remotely exploitable, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified under CWE-20. MDaemon Mail Server 23.5.2 validates SPF, DKIM, and DMARC using the email enclosed in angle brackets (<>) in the From: header of SMTP DATA. An attacker can craft a From: header with multiple invisible Unicode thin spaces to display a spoofed sender while passing validation, allowing email spoofing even when anti-spoofing protections are in place. NOTE: this is disputed by the Supplier because UI spoofing occurs in a client, not in a server such as MDaemon's product or any other server implementation. Also, if a client without its own spoofing protection must be used, the Header Screening feature in MDaemon's product can be employed to mitigate the client-side vulnerability.
Affected ProductsAI
See vendor advisory for affected versions.
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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External POC / Exploit Code
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