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GO-2025-3622 CVE-2025-31363 GHSA-9h6j-4ffx-cm84

Mattermost doesn't restrict domains LLM can request to contact upstream in github.com/mattermost/mattermost-server

Medium Go
Severity
6.5 / 10
Medium · CVSS 3.1
Exploit chance (EPSS)
0.29%
Chance of exploitation in the next 30 days. Higher than 21.41% of scored vulnerabilities.
Known exploited
No
Not in CISA's catalog
Weakness
CWE-201 Insertion of Sensitive Information Into Sent Data
CWE-497 Exposure of Sensitive System Information to an Unauthorized Control Sphere
Fix
Available
2 packages have a fixed version

Description

Mattermost doesn't restrict domains LLM can request to contact upstream in github.com/mattermost/mattermost-server

Affected versions

Go

PackageVulnerableFixed in
github.com/mattermost/mattermost-server
>= 9.11.0+incompatible, < 9.11.10+incompatible
>= 10.4.0+incompatible, < 10.4.3+incompatible
>= 10.5.0+incompatible, < 10.5.1+incompatible
9.11.10+incompatible
10.4.3+incompatible
10.5.1+incompatible
github.com/mattermost/mattermost-server/v5
all versions
No fix yet
github.com/mattermost/mattermost-server/v6
all versions
No fix yet
github.com/mattermost/mattermost/server/v8
>= 10.5.0, < 10.5.1
10.5.1
github.com/mattermost/mattermost/server/v8
>= 10.4.0, < 10.4.3
10.4.3
github.com/mattermost/mattermost/server/v8
>= 9.11.0, < 9.11.10
9.11.10
github.com/mattermost/mattermost/server/v8
< 8.0.0-20250218121836-2b5275d87136
8.0.0-20250218121836-2b5275d87136

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

github.com/mattermost/mattermost-server Go → 10.5.1+incompatible

go
go get github.com/mattermost/mattermost-server@v10.5.1+incompatible && go mod tidy

github.com/mattermost/mattermost/server/v8 Go → 10.5.1

go
go get github.com/mattermost/mattermost/server/v8@v10.5.1 && go mod tidy

Severity breakdown

CVSS 3.1 6.5

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None

Weakness

CWE-201: Insertion of Sensitive Information Into Sent Data

The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.

How to prevent it
  • Requirements: Specify which data in the software should be regarded as sensitive. Consider which types of users should have access to which types of data.
  • Implementation: Ensure that any possibly sensitive data specified in the requirements is verified with designers to ensure that it is either a calculated risk or mitigated elsewhere. Any information that is not necessary to the functionality should be removed in order to lower both the overhead and the possibility of security sensitive data being sent.
  • System Configuration: Setup default error messages so that unexpected errors do not disclose sensitive information.
  • Architecture and Design: Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

CWE-497: Exposure of Sensitive System Information to an Unauthorized Control Sphere

The product does not properly prevent sensitive system-level information from being accessed by unauthorized actors who do not have the same level of access to the underlying system as the product does.

How to prevent it
  • Architecture and Design, Implementation: Production applications should never use methods that generate internal details such as stack traces and error messages unless that information is directly committed to a log that is not viewable by the end user. All error message text should be HTML entity encoded before being written to the log file to protect against potential cross-site scripting attacks against the viewer of the logs

References

Timeline

  1. Published
  2. Last updated by the source
  3. Latest EPSS score
AdvisorySeverityWhy it's related
GHSA-xmfh-3ccg-c9fx
Mattermost has an Incorrect Authorization issue
Low Also affects github.com/mattermost/mattermost-server
GHSA-h998-hxxj-8q83
Mattermost doesn't invalidate cached authentication state for active WebSocket connections during global session revocation
Medium Also affects github.com/mattermost/mattermost-server
GHSA-g5vr-6pgg-74qv
Mattermost doesn't enforce bot-specific permission checks on the user active status endpoint
Low Also affects github.com/mattermost/mattermost-server
GHSA-jqgv-39mg-7c2r
Mattermost doesn't authenticate Atlassian Connect installed callbacks, allowing a remote unauthenticated attacker to inject a rogue sharedSecret
Medium Also affects github.com/mattermost/mattermost-server
GHSA-mxq2-5jpg-7474
Mattermost doesn't validate channel ownership of an existing subscription before applying edits
Medium Also affects github.com/mattermost/mattermost-server
GHSA-2g8v-grq3-hq2g
Mattermost doesn't enforce administrator authorization on the {{setDefaultInstance}} call within the {{/gitlab connect}} command handler
Medium Also affects github.com/mattermost/mattermost-server
GHSA-6hxm-w4hv-vgvw
Mattermost doesn't require role-management authorization when setting the scheme_admin flag on group syncable link and patch endpoints
High Also affects github.com/mattermost/mattermost-server
GHSA-9p44-r552-4wp9
Mattermost doesn't sanitize the Remote Cluster API response on PATCH operations
Medium Also affects github.com/mattermost/mattermost-server
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