CVE-2021-24663Public exploitNetwork attack vector

Administrator code execution via unchecked logo upload

Published Sep 20, 2021 · Updated Aug 3, 2024

Unrestricted file upload in Simple Schools Staff Directory 1.1 and earlier allows remote authenticated users to execute PHP code. The Add Logo page accepts a purported logo without verifying that it is an image and stores the original PHP filename under wp-content/uploads/logos. Administrator access is required; requesting the uploaded file executes arbitrary code in the WordPress server context.

CVSS severity7.2
High
EPSS probability1.49%
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 Simple Schools Staff Directory 1.1 and earlier allows remote authenticated users to execute PHP code. The Add Logo page accepts a purported logo without verifying that it is an image and stores the original PHP filename under wp-content/uploads/logos. Administrator access is required; requesting the uploaded file executes arbitrary code in the WordPress server context.

The record

CVE
CVE-2021-24663
Published
Sep 20, 2021
Updated
Aug 3, 2024
Vendor
Simple Schools
Product
Simple Schools Staff Directory
Classifications
CWE-434, T1505.003
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Sep 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.1 <=1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Simple Schools · Simple Schools Staff Directoryversion=1.1 <=1.1

Published CVSS scores

6.5NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
7.2NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-434Unrestricted Upload of File with Dangerous Type
T1505.003Server Software Component: Web Shell

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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