CVE-2026-5821

What it is

The Image Optimizer plugin for WordPress is vulnerable to arbitrary file deletion in versions up to and including 1.7.4. This is due to insufficient path validation in the Image_Backup::remove() function where backup file paths stored in post meta are used directly in file deletion operations without verifying they are within the uploads directory. The plugin stores backup file paths in the image_optimizer_metadata post meta field and trusts these paths completely when deleting backups on the delete_attachment hook. An authenticated attacker with Author-level access can edit the image_optimizer_metadata post meta on their own attachments via WordPress's Custom Fields interface, injecting arbitrary absolute file paths into the backups array. When the attacker subsequently deletes the attachment, the plugin calls File_System::delete() on each path without validation. This makes it possible for authenticated attackers, with Author-level access and above, to delete arbitrary files on the server within the web server's filesystem permissions, potentially leading to denial of service, data loss, or security degradation.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of data tampering, service disruption.

Exploit odds

0.8% chance of exploitation in the next 30 days (EPSS).

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2026-04-08 16:28 UTC ReservedThe CVE id was reserved by its CNA
2. 2026-07-02 06:16 UTC PublishedDisclosed publicly on CVE.org and NVD
3. 2026-10-28 01:16 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 0.8% in the next 30 days (EPSS).
• Severity: 8.1 HIGH (CVSS).
• Fix: none linked yet, which raises it.

Details

Published

2026-07-02 06:16 UTC

Last modified

2026-10-28 01:16 UTC

Exploit probability

0.8% · EPSS, next 30 days

Weakness

CWE-73

Record status

Deferred

Attack profile CVSS 3.1 · 8.1

Attack vector

Network

Complexity

Low

Privileges needed

Low

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

High

Availability

High

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2026-5821.md and follow it. Check whether this project is affected by CVE-2026-5821. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

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