CVE-2026-18983Network attack vector

Authenticated code execution via MIME-spoofed avatar upload

Published Aug 28, 2026 · Updated Aug 28, 2026

Unrestricted file upload in One Designs One User Avatar 2.5.4 and earlier allows remote authenticated users to execute code. The wpua_action_process_option_update path calls wp_handle_upload without a MIME allow-list, then trusts the client-supplied Content-Type after writing the file and leaves rejected files in place. Subscriber-level access reaches the upload only when an administrator enables avatar uploads for Contributors and Subscribers; accepted executable content can run in the web server context.

CVSS severityUnavailable
Unscored
EPSS probability0.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Unrestricted file upload in One Designs One User Avatar 2.5.4 and earlier allows remote authenticated users to execute code. The wpua_action_process_option_update path calls wp_handle_upload without a MIME allow-list, then trusts the client-supplied Content-Type after writing the file and leaves rejected files in place. Subscriber-level access reaches the upload only when an administrator enables avatar uploads for Contributors and Subscribers; accepted executable content can run in the web server context.

The record

CVE
CVE-2026-18983
Published
Aug 28, 2026
Updated
Aug 28, 2026
Vendor
One Designs
Product
One User Avatar
Classifications
T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 28, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 28, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=0 <=2.5.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

One Designs · One User Avatarversion=0 <=2.5.4

Published CVSS scores

No CVSS assessment is available in this record.

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 exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo