CVE-2026-5821 — Image Optimizer <= 1.7.4 - Authenticated (Author+) Arbitrary File Deletion via Post Meta Field Injection
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.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.7% (30-day exploitation probability)+8
- Technical severity (high)+6
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Elemntor Image Optimizer – Optimize Images and Convert to WebP or AVIF).
- No fix documented in the sources: reduce exposure and monitor the vendor advisory.
- Search available logs for exploit probes, errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Elemntor | Image Optimizer – Optimize Images and Convert to WebP or AVIF | ≤ 1.7.4 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 8.1 | CVSS 3.1 | High | 2.8 | 5.2 | security@wordfence.com via NIST National Vulnerability Database |
| 8.1 | CVSS 3.1 | High | — | — | Wordfence via CVE Program (cve.org) e CISA ADP |
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H (score shown at the top: security@wordfence.com) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · elemntor/image optimizer – optimize images and convert to webp or avif
- SSVC assessment updated
- Record published
- CVSS changed · 8.1
- Source status changed · → Deferred
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 15, 2026 – Oct 15, 2026
References
8 on the record
- plugins.trac.wordpress.org/browser/image-optimization/trunk/modules/backups/components/handle-ba
- plugins.trac.wordpress.org/browser/image-optimization/tags/1.7.3/classes/image/image-backup.php
- plugins.trac.wordpress.org/changeset
- plugins.trac.wordpress.org/browser/image-optimization/tags/1.7.3/classes/image/image-meta.php
- plugins.trac.wordpress.org/browser/image-optimization/tags/1.7.3/modules/backups/components/hand
- plugins.trac.wordpress.org/browser/image-optimization/trunk/classes/image/image-backup.php
- plugins.trac.wordpress.org/browser/image-optimization/trunk/classes/image/image-meta.php
- www.wordfence.com/threat-intel/vulnerabilities/id/a1a00374-e9d6-46f9-a28c-cb7768505787
Elsewhere on this site
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No fixed version, patch or mitigation documented.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-5821 is "Image Optimizer <= 1.7.4 - Authenticated (Author+) Arbitrary File Deletion via Post Meta Field Injection", rated High. It affects Image Optimizer – Optimize Images and Convert to WebP or AVIF (Elemntor); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.1 describes technical severity. EPSS 0.66% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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