HelpdeskApplication · Gfi

CVE-2026-23758

MEDIUM · 5.4 CVSS v3.1 Published 2026-04-20
Fix available
A fix is available. Upgrade to 4.99.9 or later.
See remediation →
58/100
Remediation priority · Elevated
Remotely reachable

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
GFI HelpDesk before 4.99.9 contains a stored cross-site scripting vulnerability in the ticket subject field that allows authenticated staff members to inject malicious JavaScript by manipulating the editsubject POST parameter. Attackers can inject XSS payloads through inadequate sanitization in Controller_Ticket.EditSubmit() that bypass the incomplete SanitizeForXSS() method to execute arbitrary JavaScript when other staff members or administrators view the affected ticket.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

GFI HelpDesk before version 4.99.9 contains a stored cross-site scripting vulnerability in the ticket subject field. Authenticated staff members can inject malicious JavaScript through the editsubject POST parameter in Controller_Ticket.EditSubmit() by bypassing an incomplete SanitizeForXSS() method. The injected payload executes when other staff or administrators view the affected ticket.

MitigationImplement robust input validation and context-aware output encoding in Controller_Ticket.EditSubmit() to properly sanitize the editsubject parameter, ensuring the SanitizeForXSS() method comprehensively handles all XSS vectors before storing and displaying ticket subjects.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
HelpdeskApplication
Affected:< 4.99.9

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify GFI HelpDesk installed version
    Locate the version information in the GFI HelpDesk installation - typically found in the admin panel under System Information, About, or in a version file within the installation directory. Compare the installed version number to the affected range: versions prior to 4.99.9 are vulnerable.
    Affected if Installed version is GFI HelpDesk < 4.99.9
  2. Verify staff authentication access exists
    Confirm that staff or administrator accounts exist and can log into GFI HelpDesk. The vulnerability requires an authenticated staff member to submit the malicious editsubject parameter.
    Affected if Staff or administrator accounts are active and can access the ticket management system
  3. Confirm ticket edit functionality is enabled
    Navigate to the ticket management interface and verify that staff members can edit ticket subjects. The vulnerable endpoint is Controller_Ticket.EditSubmit() which processes the editsubject POST parameter.
    Affected if Ticket editing functionality is available to authenticated staff members
  4. Inspect ticket subject display mechanism
    Examine how ticket subjects are rendered in the staff/admin ticket view pages. The stored XSS executes when viewing tickets with malicious subjects.
    Affected if Ticket subjects are displayed without proper context-aware output encoding

A user is affected if they are running GFI HelpDesk version below 4.99.9 with active staff accounts that have access to edit ticket subjects.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 4.99.9 or later
Fixed in 4.99.9
Interim mitigation

Implement robust input validation and context-aware output encoding in Controller_Ticket.EditSubmit() to properly sanitize the editsubject parameter, ensuring the SanitizeForXSS() method comprehensively handles all XSS vectors before storing and displaying ticket subjects.

Recommended fix High confidence

4.99.9

  1. Backup the current GFI Helpdesk installation and database before proceeding with the upgrade
  2. Upgrade GFI Helpdesk to version 4.99.9 or later where the stored XSS vulnerability is fixed
  3. After upgrading, verify the Controller_Ticket.EditSubmit() method now properly sanitizes the editsubject POST parameter
  4. Test that XSS payloads in the ticket subject field are properly neutralized and do not execute when viewed by other staff or administrators

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Helpdesk Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,640
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,224.

Scan for this in your stack

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-23758 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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