Mattermost
Mattermost 10.5 (ESR)
Mattermost 10.5 (ESR)
The Mattermost 10.5 (ESR) reached end of service life on Nov 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.
End of Service LifeEOSL Date: Nov 15, 2025
Issue Management
24/7 engineers own your Mattermost 10.5 (ESR) incidents end to end.
Vulnerability Remediation
Mitigation and patch-around guidance when the vendor no longer ships fixes.
Compliance Maintenance
Controls evidence and documentation that keep auditors satisfied.
Specifications
- product
- mattermost
- release
- 10.5
- product Label
- Mattermost
- release Label
- 10.5 (ESR)
- codename
- lts
- true
- latest Version
- 10.5.14
- release Date
- 2025-02-16
- maintained
- source Url
- https://endoflife.date/mattermost
Lifecycle Dates
- End of Service Life
- Nov 15, 2025
- Last OEM Support
- Nov 15, 2025
OEM vs. 3rd Party Support
See how third-party support compares to the vendor contract for Mattermost 10.5 (ESR) — 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 10.5 (ESR)?
Vulnerability Remediation
Scanning, mitigation and patch-around guidance for Mattermost 10.5 (ESR) 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 10.5 (ESR) Support: Frequently Asked Questions
Is the Mattermost 10.5 (ESR) still supported?
Mattermost ended support for the Mattermost 10.5 (ESR) on Nov 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 10.5 (ESR) end of service life (EOSL) date?
Mattermost lists the end of service life for the Mattermost 10.5 (ESR) as Nov 15, 2025.
Can I keep using the Mattermost 10.5 (ESR) 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 10.5 (ESR) 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 10.5 (ESR)
66 published CVEs affect the Mattermost 10.5 (ESR), including 8 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-2025-4981 | CRITICAL | 9.9 | Jun 20, 2025 | Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to sanitize filenames in the archive extractor which allows authenticated users to write files to arbitrary locations on the filesystem via uploading archives with path traversal sequences in filenames, potentially leading to remote code execution. The vulnerability impacts instances where file uploads and document search by content is enabled (FileSettings.EnableFileAttachments = t |
| CVE-2025-58075 | HIGH | 8.1 | Oct 16, 2025 | Mattermost versions 10.11.x <= 10.11.1, 10.10.x <= 10.10.2, 10.5.x <= 10.5.10 fail to verify a user has permission to join a Mattermost team using the original invite token which allows any attacked to join any team on a Mattermost server regardless of restrictions via manipulating the RelayState |
| CVE-2025-58073 | HIGH | 8.1 | Oct 16, 2025 | Mattermost versions 10.11.x <= 10.11.1, 10.10.x <= 10.10.2, 10.5.x <= 10.5.10 fail to verify a user has permission to join a Mattermost team using the original invite token which allows any attacked to join any team on a Mattermost server regardless of restrictions via manipulating the OAuth state. |
| CVE-2025-9079 | HIGH | 8.0 | Sep 19, 2025 | Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.10.x <= 10.10.1, 10.9.x <= 10.9.3 fail to validate import directory path configuration which allows admin users to execute arbitrary code via malicious plugin upload to prepackaged plugins directory |
| CVE-2025-9072 | HIGH | 7.6 | Sep 15, 2025 | Mattermost versions 10.10.x <= 10.10.1, 10.5.x <= 10.5.9, 10.9.x <= 10.9.4 fail to validate the redirect_to parameter, allowing an attacker to craft a malicious link that, once a user authenticates with their SAML provider, could post the user’s cookies to an attacker-controlled URL. |
| CVE-2025-25068 | HIGH | 7.5 | Mar 21, 2025 | Mattermost versions 10.4.x <= 10.4.2, 10.3.x <= 10.3.3, 9.11.x <= 9.11.8, 10.5.x <= 10.5.0 fail to enforce MFA on plugin endpoints, which allows authenticated attackers to bypass MFA protections via API requests to plugin-specific routes. |
| CVE-2025-8023 | MEDIUM | 6.8 | Aug 21, 2025 | Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2 fails to sanitize path traversal sequences in template file destination paths, which allows a system admin to perform path traversal attacks via malicious path components, potentially enabling malicious file placement outside intended directories. |
| CVE-2025-49222 | MEDIUM | 6.8 | Aug 21, 2025 | Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.9.x <= 10.9.2, 10.10.x <= 10.10.0 fail to validate upload types in remote cluster upload sessions which allows a system admin to upload non-attachment file types via shared channels that could potentially be placed in arbitrary filesystem directories. |
| CVE-2025-36530 | MEDIUM | 6.8 | Aug 21, 2025 | Mattermost versions 10.9.x <= 10.9.1, 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17 fail to properly validate file paths during plugin import operations which allows restricted admin users to install unauthorized custom plugins via path traversal in the import functionality, bypassing plugin signature enforcement and marketplace restrictions. |
| CVE-2025-6233 | MEDIUM | 6.8 | Jul 18, 2025 | Mattermost versions 10.8.x <= 10.8.1, 10.7.x <= 10.7.3, 10.5.x <= 10.5.7, 9.11.x <= 9.11.16 fail to sanitize input paths of file attachments in the bulk import JSONL file, which allows a system admin to read arbitrary system files via path traversal. |
| 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-2025-6226 | MEDIUM | 6.5 | Jul 18, 2025 | Mattermost versions 10.5.x <= 10.5.6, 10.8.x <= 10.8.1, 10.7.x <= 10.7.3, 9.11.x <= 9.11.16 fail to verify authorization when retrieving cached posts by PendingPostID which allows an authenticated user to read posts in private channels they don't have access to via guessing the PendingPostID of recently created posts. |
| CVE-2025-41395 | MEDIUM | 6.5 | Apr 24, 2025 | Mattermost versions 10.4.x <= 10.4.2, 10.5.x <= 10.5.0, 9.11.x <= 9.11.10 fail to properly validate the props used by the RetrospectivePost custom post type in the Playbooks plugin, which allows an attacker to create a specially crafted post with maliciously crafted props and cause a denial of service (DoS) of the web app for all users. |
| CVE-2025-35965 | MEDIUM | 6.5 | Apr 24, 2025 | Mattermost versions 10.4.x <= 10.4.2, 10.5.x <= 10.5.0, 9.11.x <= 9.11.10 fail to validate the uniqueness and quantity of task actions within the UpdateRunTaskActions GraphQL operation, which allows an attacker to create task items containing an excessive number of actions triggered by specific posts, overloading the server and leading to a denial-of-service (DoS) condition. |
| CVE-2025-31947 | MEDIUM | 5.8 | May 15, 2025 | Mattermost versions 10.6.x <= 10.6.1, 10.5.x <= 10.5.2, 10.4.x <= 10.4.4, 9.11.x <= 9.11.11 fail to lockout LDAP users following repeated login failures, which allows attackers to lock external LDAP accounts through repeated login failures through Mattermost. |
| 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-2025-41410 | MEDIUM | 5.4 | Oct 16, 2025 | Mattermost versions 10.10.x <= 10.10.2, 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to validate email ownership during Slack import process which allows attackers to create verified user accounts with arbitrary email domains via malicious Slack import data to bypass email-based team access restrictions |
| CVE-2025-46702 | MEDIUM | 5.4 | Jun 30, 2025 | Mattermost versions 10.5.x <= 10.5.5, 9.11.x <= 9.11.15, 10.8.x <= 10.8.0, 10.7.x <= 10.7.2, 10.6.x <= 10.6.5 fail to properly enforce channel member management permissions when adding participants to playbook runs. This allows authenticated users with member-level permissions to bypass system admin restrictions and add or remove users to/from private channels via the playbook run participants feature, even when the 'Manage Members' permission has been explicitly removed. This can lead to unauth |
Showing the 20 most severe of 66 known CVEs.
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