github.com/mattermost/mattermost-server/v6
Go214 known CVEs affecting this package
Aggregated from OSV, GitHub Security Advisories, NVD, and vendor advisories. Each CVE links to its full detail page with vendor advisories, patches, fixed versions, and remediation guidance.
CVEs affecting github.com/mattermost/mattermost-server/v6page 4 of 5
- CVE-2025-49810LOWCVSS 3.5EG 3.52025-08-21
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
- CVE-2025-53971LOWCVSS 3.8EG 3.82025-08-21
Mattermost versions 10.5.x <= 10.5.8, 9.11.x <= 9.11.17 fail to properly validate authorization for team scheme role modifications which allows Team Admins to demote Team Members to Guests via the PUT /api/v4/teams/team-id/members/user-id/…
- CVE-2025-54499LOWCVSS 3.1EG 3.12025-10-16
Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to use constant-time comparison for sensitive string comparisons which allows attackers to exploit timing oracles to perform byte-by-byte brute force attacks via response time …
- CVE-2025-55070MEDIUMCVSS 6.5EG 6.52025-11-14
Mattermost versions <11 fail to enforce multi-factor authentication on WebSocket connections which allows unauthenticated users to access sensitive information via WebSocket events
- CVE-2025-55073MEDIUMCVSS 5.4EG 5.42025-11-14
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…
- CVE-2025-55074LOWCVSS 3.0EG 3.02025-11-18
Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to enforce access permissions on the Agents plugin which allows other users to determine when users had read channels via channel member objects
- CVE-2025-58073HIGHCVSS 8.1EG 8.12025-10-16
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 …
- CVE-2025-58075HIGHCVSS 8.1EG 8.12025-10-16
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 …
- CVE-2025-6226MEDIUMCVSS 6.5EG 6.52025-07-18
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 the…
- CVE-2025-6227LOWCVSS 3.1EG 3.12025-07-18
Mattermost versions 10.5.x <= 10.5.7, 9.11.x <= 9.11.16 fail to negotiate a new token when accepting the invite which allows a user that intercepts both invite and password to send synchronization payloads to the server that originally cre…
- CVE-2025-6233MEDIUMCVSS 4.9EG 4.92025-07-18
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…
- CVE-2025-62690LOWCVSS 3.1EG 3.12025-12-17
Mattermost versions 10.11.x <= 10.11.4 fail to validate redirect URLs on the /error page, which allows an attacker to redirect a victim to a malicious site via a crafted link opened in a new tab.
- CVE-2025-64641MEDIUMCVSS 4.1EG 4.12025-12-24
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 exf…
- CVE-2025-6465MEDIUMCVSS 4.3EG 4.32025-08-21
Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 10.10.x <= 10.10.0, 10.9.x <= 10.9.3 fail to sanitize file names which allows users with file upload permission to overwrite file attachment thumbnails via path traversal in file stre…
- CVE-2025-8023MEDIUMCVSS 4.9EG 4.92025-08-21
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 ma…
- CVE-2025-8402MEDIUMCVSS 4.9EG 4.92025-08-21
Mattermost versions 10.8.x <= 10.8.3, 10.5.x <= 10.5.8, 9.11.x <= 9.11.17, 10.10.x <= 10.10.0, 10.9.x <= 10.9.3 fail to validate import data which allows a system admin to crash the server via the bulk import feature.
- CVE-2025-9072MEDIUMCVSS 5.4EG 5.42025-09-15
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 …
- CVE-2025-9076MEDIUMCVSS 6.5EG 6.52025-09-15
Mattermost versions 10.10.x <= 10.10.1 fail to properly sanitize user data during shared channel membership synchronization, which allows malicious or compromised remote clusters to access sensitive user information via unsanitized user ob…
- CVE-2025-9078MEDIUMCVSS 4.3EG 4.32025-09-15
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 properly validate cache keys for link metadata which allows authenticated users to access unauthorized posts and poison…
- CVE-2025-9079HIGHCVSS 7.2EG 7.22025-09-19
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 up…
- CVE-2025-9081MEDIUMCVSS 6.5EG 6.52025-09-19
Mattermost versions 10.5.x <= 10.5.8, 9.11.x <= 9.11.17 fail to properly validate access controls which allows any authenticated user to download sensitive files via board file download endpoint using UUID enumeration
- CVE-2025-9084MEDIUMCVSS 6.1EG 6.12025-09-15
Mattermost versions 10.5.x <= 10.5.9 fail to properly validate redirect URLs which allows attackers to redirect users to malicious sites via crafted OAuth login URLs
- CVE-2026-0999MEDIUMCVSS 4.3EG 4.32026-02-16
Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to properly validate login method restrictions which allows an authenticated user to bypass SSO-only login requirements via userID-based authentication. Matter…
- CVE-2026-20719HIGHCVSS 7.5EG 7.52026-03-25
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to prevent rendering of external SVGs on link embeds which allows unauthenticated users to crash the Mattermost webapp and desktop app via c…
- CVE-2026-21386MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to use consistent error responses when handling the /mute command which allows an authenticated team member to enumerate private channels they are not authori…
- CVE-2026-22545LOWCVSS 3.5EG 3.52026-03-16
Mattermost versions 10.11.x <= 10.11.10 fail to validate user's authentication method when processing account auth type switch which allows an authenticated attacker to change account password without confirmation via falsely claiming a di…
- CVE-2026-24458HIGHCVSS 7.5EG 7.52026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly handle very long passwords, which allows an attacker to overload the server CPU and memory via executing login attempts with multi-megabyte passwo…
- CVE-2026-2455MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to canonicalize IPv4-mapped IPv6 addresses before reserved IP validation which allows an attacker to perform SSRF attacks against internal services via IPv4-m…
- CVE-2026-2456MEDIUMCVSS 5.7EG 5.72026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 Mattermost fails to limit the size of responses from integration action endpoints, which allows an authenticated attacker to cause server memory exhaustion and den…
- CVE-2026-2457MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to sanitize client-supplied post metadata which allows an authenticated attacker to spoof permalink embeds impersonating other users via crafted PUT requests …
- CVE-2026-2458MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly validate team membership when searching channels which allows a removed team member to enumerate all public channels within a private team via the…
- CVE-2026-2463MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to filter invite IDs based on user permissions, which allows regular users to bypass access control restrictions and register unauthorized accounts via leaked…
- CVE-2026-24692MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly enforce read permissions in search API endpoints which allows guest users without read permissions to access posts and files in channels via searc…
- CVE-2026-2578MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0 fail to preserve the redacted state of burn-on-read posts during deletion which allows channel members to access unrevealed burn-on-read message contents via the WebSocket post deletion event.. Mattermo…
- CVE-2026-25780MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to bound memory allocation when processing DOC files which allows an authenticated attacker to cause server memory exhaustion and denial of service via upload…
- CVE-2026-25783MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly validate User-Agent header tokens which allows an authenticated attacker to cause a request panic via a specially crafted User-Agent header. Matte…
- CVE-2026-26246MEDIUMCVSS 4.3EG 4.32026-03-16
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to bound memory allocation when processing PSD image files which allows an authenticated attacker to cause server memory exhaustion and denial of service via …
- CVE-2026-27656MEDIUMCVSS 6.1EG 6.12026-03-25
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to properly validate user identity in the OpenID {{IsSameUser()}} comparison logic, which allows an attacker to take over arbitrary user acc…
- CVE-2026-27659MEDIUMCVSS 4.6EG 4.62026-03-25
Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to properly validate CSRF tokens in the /api/v4/access_control_policies/{policy_id}/activate endpoint, which allows an attacker to trick an …
- CVE-2026-28732MEDIUMCVSS 4.3EG 4.32026-05-18
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to enforce slash command trigger-word uniqueness during command updates which allows an authenticated team member with Manage Own Slash Commands permission to…
- CVE-2026-28741MEDIUMCVSS 6.8EG 6.82026-04-15
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which allows an attacker to update a user's authentication method via a CSRF attack by…
- CVE-2026-28759MEDIUMCVSS 4.3EG 4.32026-05-18
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate that a remote cluster has access to a channel before processing membership removal requests during shared channel membership sync, which allows a …
- CVE-2026-3108HIGHCVSS 8.8EG 8.82026-03-26
Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to sanitize user-controlled post content in the mmctl commands terminal output which allows attackers to manipulate administrator terminals …
- CVE-2026-3112MEDIUMCVSS 4.9EG 4.92026-03-26
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate Advanced Logging file target paths which allows system administrators to read arbitrary host files via malicious AdvancedLogging…
- CVE-2026-3114MEDIUMCVSS 6.5EG 6.52026-03-26
Mattermost versions 11.4.x <= 11.4.0, 11.3.x <= 11.3.1, 11.2.x <= 11.2.3, 10.11.x <= 10.11.11 fail to validate decompressed archive entry sizes during file extraction which allows authenticated users with file upload permissions to cause a…
- CVE-2026-3115MEDIUMCVSS 4.3EG 4.32026-03-26
Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to apply view restrictions when retrieving group member IDs, which allows authenticated guest users to enumerate user IDs outside their allo…
- CVE-2026-3495LOWCVSS 3.8EG 3.82026-05-18
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to escape some variables that could contain malicious content during error page composition which allows an attacker with access to edit some site configuration to execute some…
- CVE-2026-3590MEDIUMCVSS 6.5EG 6.52026-04-15
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to enforce atomic single-use consumption of guest magic link tokens, which allows an attacker with access to a valid magic link to establish…
- CVE-2026-3637MEDIUMCVSS 4.3EG 4.32026-05-18
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check the create_post channel permission during post edit operations which allows an authenticated attacker with revoked posting privileges to modify their…
- CVE-2026-4055MEDIUMCVSS 4.3EG 4.32026-05-21
Mattermost versions 11.5.x <= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via sp…
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