# CVE-2023-4386: Essential Blocks <= 4.2.0 - Unauthenticated PHP Object Injection via queries

> Unauthenticated attackers can inject PHP objects via deserialization, potentially leading to code execution or data exposure if a POP chain exists.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Oct 2023
- **Updated:** 8 Apr 2026
- **Also known as:** GHSA-w4jx-8cv4-c4v7

## What is CVE-2023-4386?

CVE-2023-4386 is a high-severity unsafe deserialization vulnerability in wpdevteam Essential Blocks Pro, published on 20 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Essential Blocks plugin for WordPress is vulnerable to PHP Object Injection in versions up to, and including, 4.2.0 via deserialization of untrusted input in the get_posts function. This allows unauthenticated attackers to inject a PHP Object. No POP chain is present in the vulnerable plugin. If a POP chain is present via an additional plugin or theme installed on the target system, it could allow the attacker to delete arbitrary files, retrieve sensitive data, or execute code.

Weakness: CWE-502 (Deserialization of Untrusted Data)

## Which versions are affected by CVE-2023-4386?

It affects 1 product.


Products: Wpdeveloper Essential Blocks.

## How do I fix CVE-2023-4386?

No fix has been published for CVE-2023-4386 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-4386 being exploited?

There is no known exploitation of CVE-2023-4386 in the wild and no public exploit code.

## Other vulnerabilities in wpdevteam Essential Blocks Pro

- [CVE-2023-6623](https://insights.sbomify.com/CVE-2023-6623/): Essential Blocks < 4.4.3 - Unauthenticated Local File Inclusion (critical 9.8)
- [CVE-2023-4402](https://insights.sbomify.com/CVE-2023-4402/): Essential Blocks <= 4.2.0 - Unauthenticated PHP Object Injection via products (high 8.1)
- [CVE-2022-47594](https://insights.sbomify.com/CVE-2022-47594/): WordPress Essential Blocks for Gutenberg plugin <= 3.8.5 - Broken Access Control (medium 6.5)
- [CVE-2023-51360](https://insights.sbomify.com/CVE-2023-51360/): WordPress Essential Blocks plugin <= 4.2.0 - Multiple Subscriber+ Broken Access Control vulnerability (medium 6.5)
- [CVE-2024-47385](https://insights.sbomify.com/CVE-2024-47385/): WordPress Essential Blocks plugin <= 4.8.4 - Cross Site Scripting (XSS) vulnerability (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-4386 and fix it if it is affected.

What it is: CVE-2023-4386 is a high-severity unsafe deserialization vulnerability in wpdevteam Essential Blocks Pro, published on 20 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-4386 in the wild and no public exploit code.

Affected product: wpdevteam Essential Blocks Pro. 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-2023-4386/ (Markdown: https://insights.sbomify.com/CVE-2023-4386/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-4386
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-4386
- OSV: https://osv.dev/vulnerability/CVE-2023-4386

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-4386/
Summaries are generated and may contain mistakes; the official description above is the record.