CVE-2020-20670Public exploitNetwork attack vector

JavaScript execution via unrestricted HTML upload

Published Sep 13, 2021 · Updated Aug 4, 2024

Unrestricted file upload in ZKEACMS 3.2.0 allows remote attackers to execute JavaScript through a crafted HTML file. The /admin/media/upload endpoint accepts a multipart file with an .html filename without rejecting the dangerous file type. Execution requires a victim to open the uploaded page, allowing attacker-controlled script content to run in that visitor's browser and support phishing.

CVSS severity8.8
High
EPSS probability1.75%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unrestricted file upload in ZKEACMS 3.2.0 allows remote attackers to execute JavaScript through a crafted HTML file. The /admin/media/upload endpoint accepts a multipart file with an .html filename without rejecting the dangerous file type. Execution requires a victim to open the uploaded page, allowing attacker-controlled script content to run in that visitor's browser and support phishing.

The record

CVE
CVE-2020-20670
Published
Sep 13, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-434, T1204.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 13, 2021CVE 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 privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-434Unrestricted Upload of File with Dangerous Type
T1204.001User Execution: Malicious Link

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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