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.
- 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
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.
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 | 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 |
3 more packages
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 include 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.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
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 Account takeover on OAuth/OpenID-enabled servers
- CVE-2025-12421 Account Takeover via Code Exchange Endpoint
- CVE-2025-4981 Path Traversal Leading to RCE by Any Authenticated Mattermost User
- CVE-2025-20051 Arbitrary file read via block duplication in Mattermost Boards
- CVE-2025-25279 Arbitrary file read in Mattermost Boards via import & export board archive
Sources
Also known as BIT-mattermost-2023-6458, GHSA-7664-hcp7-f497.