Description
Mattermost versions 11.1.x <= 11.1.0, 11.0.x <= 11.0.5, 10.12.x <= 10.12.3, 10.11.x <= 10.11.7 fail to verify that post actions invoking /share-issue-publicly were created by the Jira plugin which allowed a malicious Mattermost user to exfiltrate Jira tickets when victim users interacted with affected posts
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mattermost | Mattermost | 11.1.0 – ≤ 11.1.0, 11.0.0 – ≤ 11.0.5, 10.12.0 – ≤ 10.12.3, 10.11.0 – ≤ 10.11.7 | 11.2.0 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260723T184607-160000.1.1 | openSUSE-SU-2026:21483-1 |
| openSUSE Leap 15.6 | govulncheck-vulndb | 0.0.20260226T182644-150000.1.149.1 | SUSE-SU-2026:0757-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Go | github.com/mattermost/mattermost-server | >= 10.11.0, < 10.11.8 | 10.11.8 | GHSA-vww6-79rv-3j4x |
| Go | github.com/mattermost/mattermost-server | >= 10.12.0, < 10.12.4 | 10.12.4 | GHSA-vww6-79rv-3j4x |
| Go | github.com/mattermost/mattermost-server | >= 11.0.0, < 11.0.6 | 11.0.6 | GHSA-vww6-79rv-3j4x |
| Go | github.com/mattermost/mattermost-server | >= 11.1.0, < 11.1.1 | 11.1.1 | GHSA-vww6-79rv-3j4x |
| Go | github.com/mattermost/mattermost-server | >= 10.11.0+incompatible, < 10.11.8+incompatible · >= 10.12.0+incompatible, < 10.12.4+incompatible · >= 11.0.1+incompatible, < 11.0.6+incompatible · >= 11.1.0+incompatible, < 11.1.1+incompatible | 10.11.8+incompatible, 10.12.4+incompatible, 11.0.6+incompatible, 11.1.1+incompatible | GO-2025-4260 |
| Go | github.com/mattermost/mattermost-server/v5 | all versions | — | GO-2025-4260 |
| Go | github.com/mattermost/mattermost-server/v6 | all versions | — | GO-2025-4260 |
| Go | github.com/mattermost/mattermost/server/v8 | < 8.0.0-20251121122154-b57c297c6d7 | 8.0.0-20251121122154-b57c297c6d7 | GHSA-vww6-79rv-3j4x |
| Go | github.com/mattermost/mattermost/server/v8 | all versions | — | GO-2025-4260 |
Advisories 3
- openSUSE-SU-2026:21483-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Jul 31, 2026
- SUSE-SU-2026:0757-1 Security update for govulncheck-vulndb SUSE / openSUSE Security Updates · Mar 4, 2026
- WID-SEC-2025-2685 Mattermost: Schwachstelle ermöglicht Offenlegung von Informationen BSI CERT-Bund (WID) · Feb 26, 2026
References
- MMSA-2025-00551 vendor-advisory