HSC Cybersecurity Mailinspector up to 5.3.2-3 URL mliUserValidation.php error_description cross site scripting

Summaryinfo

A vulnerability has been found in HSC Cybersecurity Mailinspector up to 5.3.2-3 and classified as problematic. This affects an unknown part of the file /mailinspector/mliUserValidation.php of the component URL Handler. This manipulation of the argument error_description causes cross site scripting. The identification of this vulnerability is CVE-2026-3610. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. The affected component should be upgraded. The vendor was contacted early and responded very professional: "We have already implemented the fix and made a hotfix available to affected customers, ensuring mitigation while the official release 5.4.0 has not yet been published. This allows customers to address the issue immediately, outside the regular release cycle."

Detailsinfo

A vulnerability classified as problematic was found in HSC Cybersecurity Mailinspector up to 5.3.2-3. Affected by this vulnerability is an unknown part of the file /mailinspector/mliUserValidation.php of the component URL Handler. The manipulation of the argument error_description with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity.

It is possible to read the advisory at docs.google.com. This vulnerability is known as CVE-2026-3610. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details and also a public exploit are known. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

It is possible to download the exploit at docs.google.com. It is declared as proof-of-concept. The vendor was contacted early and responded very professional: "We have already implemented the fix and made a hotfix available to affected customers, ensuring mitigation while the official release 5.4.0 has not yet been published. This allows customers to address the issue immediately, outside the regular release cycle." By approaching the search of inurl:mailinspector/mliUserValidation.php it is possible to find vulnerable targets with Google Hacking.

Upgrading to version 5.4.0 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• HSC Cybersecurity

Name

• Mailinspector

Version

• 5.3.2-3

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Accepted

• Submit #748710: HSC Cybersecurity mailinspector 5.3.2-3 Cross Site Scripting (by gabriel)

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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