CVE-2025-40631: mail server (CVSS 6.1)

Description

HTTP host header injection vulnerability in Icewarp Mail Server affecting version 11.4.0. By modifying the Host header and adding a payload, arbitrary JavaScript code can be executed on page load. The user must interact with a malicious link to be redirected.

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CVSS v3.1 Score

6.1

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-644 CWE-644

Affected Products

Vendor	Product	Versions
icewarp	mail_server	All

References

Other References

https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-icewarp-mail-server

Frequently Asked Questions

What is CVE-2025-40631? +

HTTP host header injection vulnerability in Icewarp Mail Server affecting version 11.4.0. By modifying the Host header and adding a payload, arbitrary JavaScript code can be executed on page load. The user must interact with a malicious link to be redirected. It has a CVSS v3.1 base score of 6.1 (MEDIUM).

How severe is CVE-2025-40631? +

CVE-2025-40631 has a CVSS v3.1 score of 6.1 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-40631? +

CVE-2025-40631 affects products from icewarp, specifically: mail_server. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-40631? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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