Unrestricted File UploadWeakness · CWE-434

CVE-2025-31979

MEDIUM · 5.4 CVSS v3.1 Published 2025-08-28
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
60/100
Remediation priority · Elevated
Remotely reachable 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 File Upload Validation Bypass vulnerability has been identified in the HCL BigFix SM, where the application fails to properly enforce file type restrictions during the upload process. An attacker may exploit this flaw to upload malicious or unauthorized files, such as scripts, executables, or web shells, by bypassing client-side or server-side validation mechanisms.

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

HCL BigFix SM fails to properly enforce file type restrictions during the upload process, allowing attackers to bypass client-side or server-side validation mechanisms. This enables upload of malicious files including scripts, executables, and web shells.

MitigationImplement strict server-side file type validation using a deny-all/allow-list approach, verify file content/magic bytes rather than just extensions or MIME types, and restrict executable permissions on uploaded files.

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

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/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 HCL BigFix SM installation version
    Locate the BigFix SM installation directory and check version files (typically in the installation root or about dialog within the application). Compare the installed version against any available version information.
    Affected if The installed version is older than the patched version for CVE-2025-31979 or cannot be confirmed as patched.
  2. Determine if the File Upload feature is enabled
    Check the BigFix SM configuration files (typically sm.cfg, web.xml, or the web tier configuration) for upload-related settings. Look for uploadEnabled, maxUploadSize, or similar parameters.
    Affected if File upload functionality is enabled in the configuration.
  3. Review server-side file type validation settings
    Examine the web tier configuration or upload servlet settings for allowedFileTypes, fileTypeWhitelist, or content-type validation rules. Check if deny-all/allow-list is implemented.
    Affected if Server-side validation relies solely on client-side checks, MIME types, or file extensions without content/magic byte verification.
  4. Inspect uploaded files directory for suspicious content
    Locate the upload directory (commonly uploads, attachments, or temp directories in the BigFix SM data folder). List files and check for executable extensions (.exe, .bat, .sh, .jsp, .php, .asp, .ps1) or script files.
    Affected if Executable files, scripts, or web shells are present in upload directories.
  5. Check file permission settings on upload directory
    Review filesystem permissions on the upload directory. Verify if uploaded files retain executable permissions or can be executed directly from the upload location.
    Affected if Uploaded files can be executed directly or retain executable permissions.

A user is affected if HCL BigFix SM has file upload enabled and lacks proper server-side content validation using deny-all/allow-list with magic byte verification.

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 server-side file type validation using a deny-all/allow-list approach, verify file content/magic bytes rather than just extensions or MIME types, and restrict executable permissions on uploaded files.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,490
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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-2025-31979 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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