CVE-2023-1721Public exploitNetwork attack vector

Authenticated command execution via crafted thumbnail upload

Published Jun 23, 2023 · Updated Nov 27, 2024

Unrestricted file upload in Yoga Class Registration System 1.0 allows remote authenticated users to execute server commands via a thumbnail. The class thumbnail handler accepts an administrator-controlled path and extension, while images no larger than 640 by 480 pixels retain a payload-bearing PLTE chunk. Administrator access is required to place the resulting PHP file on the web server and invoke its commands remotely.

CVSS severity9.1
Critical
EPSS probability0.99%
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 Yoga Class Registration System 1.0 allows remote authenticated users to execute server commands via a thumbnail. The class thumbnail handler accepts an administrator-controlled path and extension, while images no larger than 640 by 480 pixels retain a payload-bearing PLTE chunk. Administrator access is required to place the resulting PHP file on the web server and invoke its commands remotely.

The record

CVE
CVE-2023-1721
Published
Jun 23, 2023
Updated
Nov 27, 2024
Vendor
Online Computer and Laptop Store Project
Product
Yoga Class Registration System
Classifications
CWE-434, CAPEC-650, T1505.003
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Jun 23, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 27, 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=1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Online Computer and Laptop Store Project · Yoga Class Registration Systemversion=1.0

Published CVSS scores

7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
9.1Fluid AttacksCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 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
CAPEC-650Upload a Web Shell to a Web Server
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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