CVE-2026-3610HSC Cybersecurity Mailinspector URL mliUserValidation.php cross site scripting
- 5.3MediumCVSS base score
- 0.31%Exploitation in 30 daysEPSS · top 75% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
A vulnerability was found in HSC Cybersecurity Mailinspector up to 5.3.2-3. Affected by this issue is some unknown functionality of the file /mailinspector/mliUserValidation.php of the component URL Handler. The manipulation of the argument error_description results in cross site scripting. The attack may be performed from remote. The exploit has been made public and could be used. Upgrading to version 5.4.0 can resolve this issue. You should upgrade the affected component. 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."
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit.
Show the exploits1
References tagged exploit1 reference
Timeline
ID reserved
By VulDB
- 1 day later
· 1 day later
Published
- 3 days later
· 3 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| VulDBCNA (assigner) | 4.0 | Medium5.3 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P |
| VulDBCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C |
| VulDBCNA (assigner) | 3.0 | Medium4.3 | CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N/E:P/RL:O/RC:C |
| VulDBCNA (assigner) | 2.0 | Medium5.0 | AV:N/AC:L/Au:N/C:N/I:P/A:N/E:POC/RL:OF/RC:C |
| NVDNVD · Deferred | 4.0 | Low2.1 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
- EPSS (exploitation in 30 days)
- 0.31% · top 75% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.3.
Affected products
HSC Cybersecurity · Mailinspector
- affected 5.3.2-3
- unaffected 5.4.0
References
References4
- VDB-349219 | HSC Cybersecurity Mailinspector URL mliUserValidation.php cross site scripting (opens in a new tab)vdb-entrytechnical-description
- VDB-349219 | CTI Indicators (IOB, IOC, TTP, IOA) (opens in a new tab)signaturepermissions-required
- Submit #748710 | HSC Cybersecurity mailinspector 5.3.2-3 Cross Site Scripting (opens in a new tab)third-party-advisory
- https://docs.google.com/document/d/1KI2SIDcVm5U3Yzo5tNT5YOwREQWe_5BJaWe-ctRmLoI/edit?usp=sharing (opens in a new tab)broken-linkexploit
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-9963 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-3610)Record last updated .