# CVE-2026-4431: Easy Post Submission <= 2.3.0 - Missing Authorization

> Unauthenticated attackers can modify arbitrary post content and unpublish posts due to missing capability checks in the Easy Post Submission plugin.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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:** 5 Aug 2026
- **Updated:** 5 Aug 2026
- **Also known as:** GHSA-hqvx-hxrc-x42r

## What is CVE-2026-4431?

CVE-2026-4431 is a critical missing authorization vulnerability in themeruby Easy Post Submission – Frontend Posting, Guest Publishing & Submit Content for WordPress, published on 5 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

The Easy Post Submission plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the `create_post()` function in all versions up to, and including, 2.3.0. This is due to the `rbsm_submit_post` AJAX action being registered for unauthenticated users via `wp_ajax_nopriv_rbsm_submit_post` without any authorization checks when a `postId` parameter is supplied. This makes it possible for unauthenticated attackers to modify the title, content, excerpt, categories, and tags of arbitrary posts, as well as change the post status to draft (effectively unpublishing them) via the 'postId' parameter.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-4431?


## How do I fix CVE-2026-4431?

No fix has been published for CVE-2026-4431 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-4431 being exploited?

There is no known exploitation of CVE-2026-4431 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-4431 and fix it if it is affected.

What it is: CVE-2026-4431 is a critical missing authorization vulnerability in themeruby Easy Post Submission – Frontend Posting, Guest Publishing & Submit Content for WordPress, published on 5 Aug 2026. 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-2026-4431 in the wild and no public exploit code.

Affected product: themeruby Easy Post Submission – Frontend Posting, Guest Publishing & Submit Content for WordPress. 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-2026-4431/ (Markdown: https://insights.sbomify.com/CVE-2026-4431/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-4431
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-4431
- OSV: https://osv.dev/vulnerability/CVE-2026-4431

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-4431/
Summaries are generated and may contain mistakes; the official description above is the record.