# CVE-2023-6458: Client side path traversal due to lack of route parameters validation

> An attacker can perform client-side path traversal in Mattermost by manipulating route parameters, potentially accessing unauthorized data.

- **Severity:** High 7.1 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:H/A:L`)
- **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:** Yes
- **Published:** 6 Dec 2023
- **Updated:** 2 Aug 2024
- **Also known as:** BIT-mattermost-2023-6458, GHSA-7664-hcp7-f497

## What is CVE-2023-6458?

CVE-2023-6458 is a high-severity path traversal vulnerability in Mattermost Mattermost Server, published on 6 Dec 2023. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Mattermost webapp fails to validate route parameters in/<TEAM_NAME>/channels/<CHANNEL_NAME> allowing an attacker to perform a client-side path traversal.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory), CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2023-6458?

9 open source packages ship an affected version, including github.com/mattermost/mattermost/server/v8, mattermost and github.com/mattermost/mattermost-server/v6. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/mattermost/mattermost/server/v8` | Go | All versions | 8.1.5 |
| `github.com/mattermost/mattermost/server/v8` | Go | All versions | 8.1.5 |
| `github.com/mattermost/mattermost/server/v8` | Go | From 9.0.0 | 9.0.3 |
| `github.com/mattermost/mattermost/server/v8` | Go | From 9.0.0 | 9.0.3 |
| `mattermost` | Bitnami | All versions | 7.8.14, 8.1.5, 9.0.3, 9.1.2 |
| `github.com/mattermost/mattermost-server/v6` | Go | All versions | 7.8.14 |
| `github.com/mattermost/mattermost-server/v6` | Go | All versions | 7.8.14 |
| `github.com/mattermost/mattermost/server` | Go | From 9.1.0 | 9.1.2 |
| `github.com/mattermost/mattermost/server` | Go | From 9.1.0 | 9.1.2 |

Products: Mattermost Mattermost Server.

## How do I fix CVE-2023-6458?

Upgrade github.com/mattermost/mattermost/server/v8 to a fixed version for your release line: 8.1.5 or 9.0.3.

## Is CVE-2023-6458 being exploited?

There is no known exploitation of CVE-2023-6458 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-2023-6458 and fix it if it is affected.

What it is: CVE-2023-6458 is a high-severity path traversal vulnerability in Mattermost Mattermost Server, published on 6 Dec 2023. 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-2023-6458 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/mattermost/mattermost/server/v8 (Go): affected all versions; fixed in 8.1.5
- github.com/mattermost/mattermost/server/v8 (Go): affected all versions; fixed in 8.1.5
- github.com/mattermost/mattermost/server/v8 (Go): affected from 9.0.0; fixed in 9.0.3
- github.com/mattermost/mattermost/server/v8 (Go): affected from 9.0.0; fixed in 9.0.3
- mattermost (Bitnami): affected all versions; fixed in 7.8.14, 8.1.5, 9.0.3, 9.1.2
- github.com/mattermost/mattermost-server/v6 (Go): affected all versions; fixed in 7.8.14
- github.com/mattermost/mattermost-server/v6 (Go): affected all versions; fixed in 7.8.14
- github.com/mattermost/mattermost/server (Go): affected from 9.1.0; fixed in 9.1.2
- github.com/mattermost/mattermost/server (Go): affected from 9.1.0; fixed in 9.1.2

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-2023-6458/ (Markdown: https://insights.sbomify.com/CVE-2023-6458/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-6458
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-6458
- OSV: https://osv.dev/vulnerability/CVE-2023-6458

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-6458/
Summaries are generated and may contain mistakes; the official description above is the record.