# CVE-2021-47738: CSZ CMS 1.2.7 Persistent Cross-Site Scripting via Private Messaging

> Attackers can inject malicious JavaScript into private messages via the user-agent header, leading to code execution when admins view the messages.

- **Severity:** Medium 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA: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:** 23 Dec 2025
- **Updated:** 7 Apr 2026
- **Also known as:** GHSA-ggjj-xc5q-883p

## What is CVE-2021-47738?

CVE-2021-47738 is a medium-severity cross-site scripting vulnerability in Cszcms CSZ CMS, published on 23 Dec 2025. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

CSZ CMS 1.2.7 contains a persistent cross-site scripting vulnerability that allows unauthorized users to embed malicious JavaScript in private messages. Attackers can send messages with script payloads in the user-agent header, which will execute when an admin views the message in the backend dashboard.

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

## Which versions are affected by CVE-2021-47738?

It affects 1 product.


Products: Cszcms Csz Cms.

## How do I fix CVE-2021-47738?

No fix has been published for CVE-2021-47738 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-47738 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47738 exists.

## Other vulnerabilities in Cszcms CSZ CMS

- [CVE-2024-25414](https://insights.sbomify.com/CVE-2024-25414/): File upload in n/a (critical 9.8)
- [CVE-2022-27161](https://insights.sbomify.com/CVE-2022-27161/): SQL injection in n/a (critical 9.8)
- [CVE-2022-27162](https://insights.sbomify.com/CVE-2022-27162/): SQL injection in n/a (critical 9.8)
- [CVE-2022-27163](https://insights.sbomify.com/CVE-2022-27163/): SQL injection in n/a (critical 9.8)
- [CVE-2022-27164](https://insights.sbomify.com/CVE-2022-27164/): SQL injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-47738 and fix it if it is affected.

What it is: CVE-2021-47738 is a medium-severity cross-site scripting vulnerability in Cszcms CSZ CMS, published on 23 Dec 2025. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47738 exists.

Affected product: Cszcms CSZ CMS. 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-2021-47738/ (Markdown: https://insights.sbomify.com/CVE-2021-47738/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47738
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47738
- OSV: https://osv.dev/vulnerability/CVE-2021-47738

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47738/
Summaries are generated and may contain mistakes; the official description above is the record.