# CVE-2026-91051: EWWW Image Optimizer 8.6.0 - 8.7.7 - Author+ PHP Object Injection via 'eio_page_settings' Post Meta

> Authenticated authors can trigger PHP object injection via post meta, potentially leading to remote code execution if gadget chains exist.

- **Severity:** Medium 6.6 (`CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 30 Sep 2026
- **Updated:** 30 Sep 2026
- **Also known as:** GHSA-rhvr-pxgv-9rpq

## What is CVE-2026-91051?

CVE-2026-91051 is a medium-severity unsafe deserialization vulnerability in Unknown EWWW Image Optimizer, published on 30 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

The EWWW Image Optimizer WordPress plugin before 8.8.0 does not prevent authenticated users with author-level permissions from storing a serialized value in a post meta field that is deserialized when the post is rendered, allowing them to perform PHP Object Injection, which can lead to remote code execution when a suitable gadget chain is present via another installed EWWW Image Optimizer WordPress plugin before 8.8.0 or .

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2026-91051?


## How do I fix CVE-2026-91051?

No fix has been published for CVE-2026-91051 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-91051 being exploited?

There is no known exploitation of CVE-2026-91051 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-91051 and fix it if it is affected.

What it is: CVE-2026-91051 is a medium-severity unsafe deserialization vulnerability in Unknown EWWW Image Optimizer, published on 30 Sep 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-91051 in the wild and no public exploit code.

Affected product: Unknown EWWW Image Optimizer. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-91051/ (Markdown: https://insights.sbomify.com/CVE-2026-91051/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-91051
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-91051
- OSV: https://osv.dev/vulnerability/CVE-2026-91051

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-91051/
Summaries are generated and may contain mistakes; the official description above is the record.