# CVE-2021-24918: Smash Balloon Social Post Feed < 4.0.1 - Subscriber+ Arbitrary Plugin Settings Update to Stored XSS

> Logged-in users can inject malicious JavaScript into plugin settings, leading to stored XSS attacks on site posts and pages.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 29 Nov 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-j9qp-w82r-g5cf

## What is CVE-2021-24918?

CVE-2021-24918 is a medium-severity cross-site scripting vulnerability in Unknown Smash Balloon Social Post Feed, published on 29 Nov 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

The Smash Balloon Social Post Feed WordPress plugin before 4.0.1 did not have any privilege or nonce validation before saving the plugin's setting. As a result, any logged-in user on a vulnerable site could update the settings and store rogue JavaScript on each of its posts and pages.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2021-24918?

It affects 1 product.


Products: Smashballoon Smash Balloon Social Post Feed.

## How do I fix CVE-2021-24918?

No fix has been published for CVE-2021-24918 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-24918 being exploited?

There is no known exploitation of CVE-2021-24918 in the wild and no public exploit code.

## Other vulnerabilities in Unknown Smash Balloon Social Post Feed

- [CVE-2021-24508](https://insights.sbomify.com/CVE-2021-24508/): Smash Balloon Social Post Feed < 2.19.2 - Unauthenticated Stored XSS (medium 6.1)
- [CVE-2022-4477](https://insights.sbomify.com/CVE-2022-4477/): Smash Balloon Social Post Feed < 4.1.6 - Contributor+ Stored XSS (medium 5.4)
- [CVE-2021-25065](https://insights.sbomify.com/CVE-2021-25065/): Smash Balloon Social Post Feed < 4.1.1 - Authenticated Reflected Cross-Site Scripting (XSS) (medium 5.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-24918 and fix it if it is affected.

What it is: CVE-2021-24918 is a medium-severity cross-site scripting vulnerability in Unknown Smash Balloon Social Post Feed, published on 29 Nov 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-24918 in the wild and no public exploit code.

Affected product: Unknown Smash Balloon Social Post Feed. 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-2021-24918/ (Markdown: https://insights.sbomify.com/CVE-2021-24918/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-24918
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-24918
- OSV: https://osv.dev/vulnerability/CVE-2021-24918

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From sbomify Insights: https://insights.sbomify.com/CVE-2021-24918/
Summaries are generated and may contain mistakes; the official description above is the record.