Mattermost 10.12
Mattermost 10.12
The Mattermost 10.12 reached end of service life on Dec 15, 2025 — Mattermost no longer ships security patches or fixes for it. Our third-party support keeps it safe to run: 24/7 engineers manage issues, remediate vulnerabilities, and help you maintain compliance.
24/7 engineers own your Mattermost 10.12 incidents end to end.
Mitigation and patch-around guidance when the vendor no longer ships fixes.
Controls evidence and documentation that keep auditors satisfied.
Specifications
- product
- mattermost
- release
- 10.12
- product Label
- Mattermost
- release Label
- 10.12
- codename
- lts
- latest Version
- 10.12.4
- release Date
- 2025-09-16
- maintained
- source Url
- https://endoflife.date/mattermost
Lifecycle Dates
- End of Service Life
- Dec 15, 2025
- Last OEM Support
- Dec 15, 2025
OEM vs. 3rd Party Support
See how third-party support compares to the vendor contract for Mattermost 10.12 — monitoring, break/fix, vulnerability work, operations and compliance, before and after EOSL.
| Feature | OEM Support | 3rd Party Support |
|---|---|---|
| Post-EOSL Support | ||
| Break/Fix Support | Until EOSL | |
| 24/7 Monitoring | ||
| Vulnerability Scanning & Remediation | ||
| Managed Operations | ||
| Procedure & Configuration Review | ||
| Compliance & Audit Documentation | Limited | |
| Discounted Migration to Other Platforms |
Why Choose 3rd Party Support for Mattermost 10.12?
Vulnerability Remediation
Scanning, mitigation and patch-around guidance for Mattermost 10.12 when the vendor no longer ships fixes.
Compliance Maintenance
Procedure review, controls evidence and the documentation auditors ask for — maintained continuously, not scrambled at audit time.
24/7 Expert Support
Engineers who know this release monitor, manage and fix issues around the clock — break/fix to managed operations.
Mattermost 10.12 Support: Frequently Asked Questions
Is the Mattermost 10.12 still supported?
Mattermost ended support for the Mattermost 10.12 on Dec 15, 2025 — no more patches or fixes from the vendor. Third-party support keeps it covered: our engineers manage issues, remediate vulnerabilities, and help you maintain compliance for as long as you run it.
When is the Mattermost 10.12 end of service life (EOSL) date?
Mattermost lists the end of service life for the Mattermost 10.12 as Dec 15, 2025.
Can I keep using the Mattermost 10.12 after its EOSL date?
Yes. EOSL means Mattermost stops issuing patches and support — the software itself keeps running. Third-party support covers it from there: issue management, security vulnerability remediation, and the compliance documentation auditors ask for, for as long as you choose to run it.
How much does third-party support for the Mattermost 10.12 cost?
Typically 40-70% below the OEM maintenance renewal price. Exact pricing depends on quantity, service level and location — request a quote and we respond within 24 hours.
Known Vulnerabilities Affecting Mattermost 10.12
15 published CVEs affect the Mattermost 10.12, including 3 rated critical or high severity. Mattermost no longer ships security patches for this release — our engineers provide mitigation guidance, workarounds and hardening support.
| CVE | Severity | CVSS | Published | Summary |
|---|---|---|---|---|
| CVE-2025-12421 | CRITICAL | 9.9 | Nov 27, 2025 | Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to to verify that the token used during the code exchange originates from the same authentication flow, which allows an authenticated user to perform account takeover via a specially crafted email address used when switching authentication methods and sending a request to the /users/login/sso/code-exchange endpoint. The vulnerability requires ExperimentalEnableAuthenticationTransfer to be enabled |
| CVE-2025-12419 | CRITICAL | 9.9 | Nov 27, 2025 | Mattermost versions 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12, 11.0.x <= 11.0.3 fail to properly validate OAuth state tokens during OpenID Connect authentication which allows an authenticated attacker with team creation privileges to take over a user account via manipulation of authentication data during the OAuth completion flow. This requires email verification to be disabled (default: disabled), OAuth/OpenID Connect to be enabled, and the attacker to control two users in the S |
| CVE-2025-14273 | HIGH | 7.2 | Dec 22, 2025 | 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 with the Jira plugin enabled and Mattermost Jira plugin versions <=4.4.0 fail to enforce authentication and issue-key path restrictions in the Jira plugin, which allows an unauthenticated attacker who knows a valid user ID to issue authenticated GET and POST requests to the Jira server via crafted plugin payloads that spoof the user ID and inject arbitrary issue key paths. Mattermost Advisory ID: MMSA- |
| CVE-2025-12689 | MEDIUM | 6.5 | Dec 17, 2025 | Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request. |
| CVE-2025-55070 | MEDIUM | 6.5 | Nov 14, 2025 | Mattermost versions <11 fail to enforce multi-factor authentication on WebSocket connections which allows unauthenticated users to access sensitive information via WebSocket events |
| CVE-2025-55073 | MEDIUM | 5.4 | Nov 14, 2025 | Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11, 10.12.x <= 10.12.0 fail to validate the relationship between the post being updated and the MSTeams plugin OAuth flow which allows an attacker to edit arbitrary posts via a crafted MSTeams plugin OAuth redirect URL. |
| CVE-2025-11794 | MEDIUM | 4.9 | Nov 14, 2025 | Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11, 10.12.x <= 10.12.0 fail to sanitize user data which allows system administrators to access password hashes and MFA secrets via the POST /api/v4/users/{user_id}/email/verify/member endpoint |
| CVE-2025-13767 | MEDIUM | 4.3 | Dec 24, 2025 | 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 fails to validate user channel membership when attaching Mattermost posts as comments to Jira issues, which allows an authenticated attacker with access to the Jira plugin to read post content and attachments from channels they do not have access to. |
| CVE-2025-62190 | MEDIUM | 4.3 | Dec 17, 2025 | Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 and Mattermost Calls versions <=1.10.0 fail to implement CSRF protection on the Calls widget page which allows an authenticated attacker to initiate calls and inject messages into channels or direct messages via a malicious webpage or crafted link |
| CVE-2025-12756 | MEDIUM | 4.3 | Dec 1, 2025 | Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to validate user permissions when deleting comments in Boards, which allows an authenticated user with the editor role to delete comments created by other users. |
| CVE-2025-12559 | MEDIUM | 4.3 | Nov 27, 2025 | Mattermost versions 11.0.x <= 11.0.2, 10.12.x <= 10.12.1, 10.11.x <= 10.11.4, 10.5.x <= 10.5.12 fail to sanitize team email addresses to be visible only to Team Admins, which allows any authenticated user to view team email addresses via the GET /api/v4/channels/{channel_id}/common_teams endpoint |
| CVE-2025-11776 | MEDIUM | 4.3 | Nov 14, 2025 | Mattermost versions <11 fail to properly restrict access to archived channel search API which allows guest users to discover archived public channels via the `/api/v4/teams/{team_id}/channels/search_archived` endpoint |
| CVE-2025-64641 | MEDIUM | 4.1 | Dec 24, 2025 | 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 |
| CVE-2025-13324 | LOW | 3.7 | Dec 17, 2025 | Mattermost versions 10.11.x <= 10.11.5, 11.0.x <= 11.0.4, 10.12.x <= 10.12.2 fail to invalidate remote cluster invite tokens when using the legacy (version 1) protocol or when the confirming party does not provide a refreshed token, which allows an attacker who has obtained an invite token to authenticate as the remote cluster and perform limited actions on shared channels even after the invitation has been legitimately confirmed. |
| CVE-2025-41436 | LOW | 3.1 | Nov 14, 2025 | Mattermost versions <11.0 fail to properly enforce the "Allow users to view archived channels" setting which allows regular users to access archived channel content and files via the "Open in Channel" functionality from followed threads |