dbcve.org
Improper Access ControlWeakness · CWE-284

CVE-2026-4830

MEDIUM · 5.6 CVSS v3.1 Published 2026-03-26
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
65/100
Remediation priority · Elevated
Remotely reachable No privileges Zero-click

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
A vulnerability was identified in kalcaddle kodbox 1.64. This issue affects the function Add of the file app/controller/explorer/userShare.class.php of the component Public Share Handler. Such manipulation leads to unrestricted upload. The attack can be executed remotely. This attack is characterized by high complexity. The exploitability is assessed as difficult. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

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 · moderate confidence

Unrestricted file upload vulnerability in the Add function of userShare.class.php within the Public Share Handler component of kodbox 1.64. Attackers can remotely upload arbitrary files due to insufficient validation in the share creation process.

MitigationImplement strict file type validation, content-based verification, and store uploaded files outside the webroot or with restrictive access controls. Consider adding authentication requirements and rate limiting to the share creation endpoint.

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

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
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
Low

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

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. Verify kodbox version
    Access the kodbox admin interface and navigate to Settings > About, or check the version file in the installation directory (such as config/version.php or similar version indicator).
    Affected if The installed version is exactly 1.64, as this is the only version listed as affected.
  2. Confirm Public Share Handler is accessible
    Attempt to access the public share creation functionality. This is typically found at a URL path containing 'share' or 'public' in the kodbox web interface. Verify the endpoint is reachable without authentication if the vulnerability allows unauthenticated exploitation.
    Affected if The Public Share Handler feature is enabled and accessible to the attacker (whether authenticated or not).
  3. Inspect the vulnerable file integrity
    Locate userShare.class.php within the kodbox installation directory (likely in a src/ or app/ handler path). Verify the file has not been modified by comparing its hash or modification timestamp to a known clean version from the vendor.
    Affected if The file is present and unmodified from the vulnerable 1.64 release, indicating the insufficient validation still exists.
  4. Check for suspicious uploaded files
    Review directories where share files might be stored (commonly under data/ or storage/ directories). Look for files with executable extensions (.php, .phtml, .exe, .sh) or unexpected file types that were not intentionally uploaded.
    Affected if Executable or suspicious files exist in share-related storage directories that were not intentionally placed there by legitimate administrators.
  5. Review access and upload logs
    Examine kodbox access logs and any application-level logs for the share creation endpoint. Look for repeated POST requests to the share Add function with unusual file types or unusual request patterns.
    Affected if Logs show anomalous upload requests to the share handler, particularly with file types that should be blocked by proper validation.

A user is affected if they are running kodbox version 1.64 with the Public Share Handler feature enabled and accessible, without modifications to the vulnerable userShare.class.php file.

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.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Implement strict file type validation, content-based verification, and store uploaded files outside the webroot or with restrictive access controls. Consider adding authentication requirements and rate limiting to the share creation endpoint.

Have this fixed Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing2.0 h
  • Review / QA1.0 h
9.0 hours of engineering $1,600
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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-2026-4830 in production — separate from our analysis above.

No notes yet

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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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