# CVE-2023-36816: Cross-Site Scripting (XSS) at Account creation in 2FAuth

> Attackers can inject malicious scripts via the account/service field in 2FAuth, potentially compromising user sessions and data.

- **Severity:** Medium 6.1 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 3 Jul 2023
- **Updated:** 22 Nov 2024
- **Also known as:** GHSA-cwhq-2mcq-pp9q

## What is CVE-2023-36816?

CVE-2023-36816 is a medium-severity cross-site scripting vulnerability in Bubka 2FAuth, published on 3 Jul 2023. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

2FA is a Web app to manage Two-Factor Authentication (2FA) accounts and generate their security codes. Cross site scripting (XSS) injection can be done via the account/service field. This was tested in docker-compose environment. This vulnerability has been patched in version 4.0.3.

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

## Which versions are affected by CVE-2023-36816?

It affects 1 product.


Products: 2fauth 2fauth.

## How do I fix CVE-2023-36816?

No fix has been published for CVE-2023-36816 yet. Limit exposure of the affected software until one is available.

## Is CVE-2023-36816 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2023-36816 exists.

## Other vulnerabilities in Bubka 2FAuth

- [CVE-2026-32133](https://insights.sbomify.com/CVE-2026-32133/): 2FAuth has Blind SSRF in image parameter allows internal network access and more (high 7.8)
- [CVE-2024-52598](https://insights.sbomify.com/CVE-2024-52598/): 2FAuth vulnerable to Server Side Request Forgery + URI validation bypass in 2fauth /api/v1/twofaccounts/preview (high 7.5)
- [CVE-2025-45731](https://insights.sbomify.com/CVE-2025-45731/): Race condition in n/a (medium 6.5)
- [CVE-2024-52597](https://insights.sbomify.com/CVE-2024-52597/): 2FAuth vulnerable to stored cross-site scripting via SVG upload and direct access render (medium 6.1)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-36816 and fix it if it is affected.

What it is: CVE-2023-36816 is a medium-severity cross-site scripting vulnerability in Bubka 2FAuth, published on 3 Jul 2023. It can only be exploited from the same machine or local 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-2023-36816 exists.

Affected product: Bubka 2FAuth. 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-2023-36816/ (Markdown: https://insights.sbomify.com/CVE-2023-36816/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-36816
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-36816
- OSV: https://osv.dev/vulnerability/CVE-2023-36816

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-36816/
Summaries are generated and may contain mistakes; the official description above is the record.