CVE-2025-24526 is a medium-severity (CVSS 4.3) CWE-863 vulnerability in github.com/mattermost/mattermost/server/v8. A fix is available for github.com/mattermost/mattermost/server/v8 — see the affected versions and patch details below.
Channel export permitted on archived channel when viewing archived channels is disabled
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2025-24526.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8🐹github.com/mattermost/mattermost/server/v8Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Mattermost versions 10.1.x <= 10.1.3, 10.4.x <= 10.4.1, 9.11.x <= 9.11.7, 10.3.x <= 10.3.2, 10.2.x <= 10.2.2 fail to restrict channel export of archived channels when the "Allow users to view archived channels" is disabled which allows a user to export channel contents when they shouldn't have access to it
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/mattermost/mattermost/server/v8 | all versions | 8.0.0-20250110161910-96195f1bd746go get github.com/mattermost/mattermost/server/v8@v8.0.0-20250110161910-96195f1bd746 |
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 9.11.0-rc1&&< 9.11.8 | 9.11.8go get github.com/mattermost/mattermost/server/v8@v9.11.8 |
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 10.2.0-rc1&&< 10.2.3 | 10.2.3go get github.com/mattermost/mattermost/server/v8@v10.2.3 |
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 10.3.0-rc1&&< 10.3.3 | 10.3.3go get github.com/mattermost/mattermost/server/v8@v10.3.3 |
| 🐹Go | github.com/mattermost/mattermost/server/v8 | ≥ 10.4.0-rc1&&< 10.4.2 | 10.4.2go get github.com/mattermost/mattermost/server/v8@v10.4.2 |
Affected Products
mattermost servermattermostDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/mattermost/mattermost/server/v8, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/mattermost/mattermost/server/v8 to 8.0.0-20250110161910-96195f1bd746 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-24526 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.
Frequently Asked Questions
Is CVE-2025-24526 in your dependencies?
Find it across Go, including transitive dependencies.