CVE-2020-5188Public exploitNetwork attack vector

Administrator-only file upload via client-side validation bypass

Published Feb 24, 2020 · Updated Aug 4, 2024

File-upload authorization bypass in DNN through 9.4.4 allows remote authenticated users to upload administrator-only file types. The shared file-upload module enforces its extra normal-user extension restrictions only in client-side code, while the server applies an extension allowlist only for superusers. Any normal authenticated account can alter the request to store file types reserved for superusers, enabling unauthorized application-content modification.

CVSS severity6.5
Medium
EPSS probability1.81%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

File-upload authorization bypass in DNN through 9.4.4 allows remote authenticated users to upload administrator-only file types. The shared file-upload module enforces its extra normal-user extension restrictions only in client-side code, while the server applies an extension allowlist only for superusers. Any normal authenticated account can alter the request to store file types reserved for superusers, enabling unauthorized application-content modification.

The record

CVE
CVE-2020-5188
Published
Feb 24, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-669, CWE-434
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 24, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
4.0NIST NVDAV:N/AC:L/Au:S/C:N/I:P/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-669Incorrect Resource Transfer Between Spheres
CWE-434Unrestricted Upload of File with Dangerous Type

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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