# CVE-2024-5270: SAML to email switch possible when email signin is disabled

> Attackers can bypass SAML authentication restrictions to switch to email login and modify protected profile fields in Mattermost.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 26 May 2024
- **Updated:** 1 Aug 2024

## What is CVE-2024-5270?

CVE-2024-5270 is a medium-severity authentication bypass vulnerability in Mattermost Mattermost Server, published on 26 May 2024. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Mattermost versions 9.5.x <= 9.5.3, 9.7.x <= 9.7.1, 9.6.x <= 9.6.1 and 8.1.x <= 8.1.12 fail to check if the email signup configuration option is enabled when a user requests to switch from SAML to Email. This allows the user to switch their authentication mail from SAML to email and possibly edit personal details that were otherwise non-editable and provided by the SAML provider.

Weakness: CWE-284 (Improper Access Control)

## Which versions are affected by CVE-2024-5270?

It affects 1 product.


Products: Mattermost Mattermost Server.

## How do I fix CVE-2024-5270?

No fix has been published for CVE-2024-5270 yet. Limit exposure of the affected software until one is available.

## Is CVE-2024-5270 being exploited?

There is no known exploitation of CVE-2024-5270 in the wild and no public exploit code.

## Other vulnerabilities in Mattermost Mattermost Server

- [CVE-2025-12419](https://insights.sbomify.com/CVE-2025-12419/): Account takeover on OAuth/OpenID-enabled servers (critical 9.9)
- [CVE-2025-12421](https://insights.sbomify.com/CVE-2025-12421/): Account Takeover via Code Exchange Endpoint (critical 9.9)
- [CVE-2025-4981](https://insights.sbomify.com/CVE-2025-4981/): Path Traversal Leading to RCE by Any Authenticated Mattermost User (critical 9.9)
- [CVE-2025-20051](https://insights.sbomify.com/CVE-2025-20051/): Arbitrary file read via block duplication in Mattermost Boards (critical 9.9)
- [CVE-2025-25279](https://insights.sbomify.com/CVE-2025-25279/): Arbitrary file read in Mattermost Boards via import & export board archive (critical 9.9)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-5270 and fix it if it is affected.

What it is: CVE-2024-5270 is a medium-severity authentication bypass vulnerability in Mattermost Mattermost Server, published on 26 May 2024. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-5270 in the wild and no public exploit code.

Affected product: Mattermost Mattermost Server. 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-2024-5270/ (Markdown: https://insights.sbomify.com/CVE-2024-5270/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-5270
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-5270
- OSV: https://osv.dev/vulnerability/CVE-2024-5270

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-5270/
Summaries are generated and may contain mistakes; the official description above is the record.