GO-2024-2706 BIT-mattermost-2024-29221 CVE-2024-29221 GHSA-w67v-ph4x-f48q

Mattermost Server Improper Access Control in github.com/mattermost/mattermost-server

Low Go

Severity: 0.0 / 10; Low · CVSS 4.0
Exploit chance (EPSS): 0.33%; Chance of exploitation in the next 30 days. Higher than 26.33% of scored vulnerabilities.
Known exploited: No; Not in CISA's catalog
Weakness: CWE-284 Improper Access Control
Fix: Available; 2 packages have a fixed version

Description

Mattermost Server Improper Access Control in github.com/mattermost/mattermost-server.

NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions.

(If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.)

The additional affected modules and versions are: github.com/mattermost/mattermost/server/v8 from v8.1.0 before v8.1.11.

Affected versions

Go

Package	Vulnerable	Fixed in
github.com/mattermost/mattermost-server	`>= 9.3.0+incompatible, < 9.3.3+incompatible` `>= 9.4.0+incompatible, < 9.4.4+incompatible` `>= 9.5.0+incompatible, < 9.5.2+incompatible`	`9.3.3+incompatible` `9.4.4+incompatible` `9.5.2+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	`>= 8.1.0, < 8.1.11`	`8.1.11`
github.com/mattermost/mattermost/server/v8	`>= 9.5.0, < 9.5.2`	`9.5.2`
github.com/mattermost/mattermost/server/v8	`>= 9.4.0, < 9.4.4`	`9.4.4`
github.com/mattermost/mattermost/server/v8	`>= 9.3.0, < 9.3.3`	`9.3.3`
github.com/mattermost/mattermost/server/v8	`all versions`	No fix yet

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 → `9.5.2+incompatible`

go

go get github.com/mattermost/mattermost-server@v9.5.2+incompatible && go mod tidy

github.com/mattermost/mattermost/server/v8 Go → `8.1.11`

go

go get github.com/mattermost/mattermost/server/v8@v8.1.11 && go mod tidy

Severity breakdown

CVSS 4.0 0.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N

Attack vector: Network
Attack complexity: Low
Attack requirements: None
Privileges required: High
User interaction: None
Confidentiality (vulnerable system): Low
Integrity (vulnerable system): Low
Availability (vulnerable system): Low
Confidentiality (subsequent systems): None
Integrity (subsequent systems): None
Availability (subsequent systems): None

CVSS 3.1 3.8

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

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

Weakness

CWE-284: Improper Access Control

The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor.

How to prevent it

Architecture and Design, Operation: Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
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.

References

Advisories

Packages

github.com/mattermost/mattermost

Timeline

Apr 5, 2024 Published
Jun 17, 2026 Last updated by the source
Nov 1, 2026 Latest EPSS score

Advisory	Severity	Why 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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