CVE-2021-24252Public exploitNetwork attack vector

Code execution via unrestricted image upload

Published May 5, 2021 · Updated Aug 3, 2024

Arbitrary file upload in denovembre Event Banner 1.3 and earlier allows remote authenticated users to execute code via an uploaded PHP file. The administrative banner form's upload handler accepts the multipart image field and stores its filename and contents under wp-content/uploads/event_banner without checking the file type. Direct exploitation requires an administrator session; absent CSRF checks also let context-dependent attackers induce an administrator to submit the upload, after which the PHP file is web-accessible.

CVSS severity7.2
High
EPSS probability1.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Arbitrary file upload in denovembre Event Banner 1.3 and earlier allows remote authenticated users to execute code via an uploaded PHP file. The administrative banner form's upload handler accepts the multipart image field and stores its filename and contents under wp-content/uploads/event_banner without checking the file type. Direct exploitation requires an administrator session; absent CSRF checks also let context-dependent attackers induce an administrator to submit the upload, after which the PHP file is web-accessible.

The record

CVE
CVE-2021-24252
Published
May 5, 2021
Updated
Aug 3, 2024
Vendor
denovembre
Product
Event Banner
Classifications
CWE-434, T1190
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. May 5, 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=1.3 <=1.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

denovembre · Event Bannerversion=1.3 <=1.3

Published CVSS scores

7.2NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/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 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
T1190Exploit Public-Facing Application

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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