CVE-2025-40631

low-risk

Published 2025-05-16

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.

Do I need to act?

0.19% chance of exploitation

EPSS score — low exploit probability

Not on CISA KEV list

No confirmed active exploitation reported to CISA

Patch status unknown

Check vendor advisories for fix availability and mitigation guidance

CVSS 6.1/10 Medium

NETWORK / LOW complexity

Affected Products (1)

Mail Server

Affected Vendors

Icewarp

References (1)

Third Party Advisory https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-icew...

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low-risk

Severity 23/34 · High

Exploitability 1/34 · Minimal

Exposure 5/34 · Minimal