# CVE-2023-53976: myBB Forums 1.8.26 Stored Cross-Site Scripting via Template Management

> Authenticated administrators can inject malicious scripts via template titles, leading to arbitrary JavaScript execution when viewed.

- **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:** 22 Dec 2025
- **Updated:** 7 Apr 2026
- **Also known as:** GHSA-wf3v-cq62-6r54

## What is CVE-2023-53976?

CVE-2023-53976 is a medium-severity cross-site scripting vulnerability in Mybb Mybb, published on 22 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

myBB Forums 1.8.26 contains a stored cross-site scripting vulnerability in the template management system that allows authenticated administrators to inject malicious scripts when creating new templates. Attackers can exploit this vulnerability by inserting script payloads in the template title field when adding new templates through the 'Templates and Style' > 'Templates' > 'Manage Templates' > 'Global Templates' interface, causing arbitrary JavaScript to execute when the template is viewed.

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

## Which versions are affected by CVE-2023-53976?

It affects 1 product.


Products: Mybb Mybb.

## How do I fix CVE-2023-53976?

No fix has been published for CVE-2023-53976 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-53976 being exploited?

There is no known exploitation of CVE-2023-53976 in the wild and no public exploit code.

## Other vulnerabilities in Mybb Mybb

- [CVE-2011-10018](https://insights.sbomify.com/CVE-2011-10018/): myBB 1.6.4 Backdoor Arbitrary Command Execution (critical 10.0)
- [CVE-2015-2786](https://insights.sbomify.com/CVE-2015-2786/): Information disclosure in n/a (critical 10.0)
- [CVE-2011-5133](https://insights.sbomify.com/CVE-2011-5133/): Cross-site scripting in n/a (critical 10.0)
- [CVE-2006-0218](https://insights.sbomify.com/CVE-2006-0218/): SQL injection in n/a (critical 10.0)
- [CVE-2020-22612](https://insights.sbomify.com/CVE-2020-22612/): Code injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-53976 and fix it if it is affected.

What it is: CVE-2023-53976 is a medium-severity cross-site scripting vulnerability in Mybb Mybb, published on 22 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: There is no known exploitation of CVE-2023-53976 in the wild and no public exploit code.

Affected product: Mybb Mybb. 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-2023-53976/ (Markdown: https://insights.sbomify.com/CVE-2023-53976/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-53976
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-53976
- OSV: https://osv.dev/vulnerability/CVE-2023-53976

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-53976/
Summaries are generated and may contain mistakes; the official description above is the record.