Vulnerability database
Every flaw the U.S. government’s cybersecurity agency (CISA) has confirmed attackers are using, plus the new WordPress plugin and theme bugs published each day, sorted by what they mean for a small business. We refresh it twice a day. If you see something your website or office runs, tell us.
676 results · page 2 of 14
Aug 17, 2026Mattermost Plugins versions <=11.8 10.20.11 11.5.7.0 _The Mattermost GitLab plugin fails to verify channel permissions when processing API requests with a calleCVE-2026-16049 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost Plugins versions <=11.8 10.20.11 11.5.7.0 _The Mattermost GitLab plugin fails to verify channel permissions when processing API requests with a caller-supplied_ {{post_id}}_, and fails to validate the_ {{web_url}} _parameter against the configured GitLab instance, which allows an authenticated attacker to inject bot-authored messages containing arbitrary URLs into channels they do not have access to via the_ {{createIssue}} _and_ {{attachCommentToIssue}} _API endpoints._ Mattermost Advisory ID: MMSA-2026-00673
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 17, 2026Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allowsCVE-2026-16048 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.3
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 17, 2026Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fail to validate that users have read access to a channel before linking a board to CVE-2026-16047 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fail to validate that users have read access to a channel before linking a board to it, which allows an authenticated attacker to discover the membership of private channels on the same team via creating, patching, importing, or bulk-creating boards with an arbitrary channelId. Mattermost Advisory ID: MMSA-2026-00674
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 17, 2026Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to enforce run-state validation on write operations for finished playbook runs which allows a runCVE-2026-16046 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to enforce run-state validation on write operations for finished playbook runs which allows a run participant to modify status, checklists, retrospective content, ownership, and participants on completed runs via REST and GraphQL API requests. Mattermost Advisory ID: MMSA-2026-00675
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 17, 2026Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 Mattermost failed to restrict OAuth deauthorization and personal access token management endpoints to CVE-2026-16045 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 Mattermost failed to restrict OAuth deauthorization and personal access token management endpoints to direct user sessions, which allowed an OAuth app with a delegated user token to revoke the user's authorizations or tokens for other integrations via account-management endpoints.. Mattermost Advisory ID: MMSA-2026-00704
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 17, 2026Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which alCVE-2026-16044 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.4
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to prevent guest users from receiving Board Admin privileges during board archive import which allows a board member to escalate a guest user to Board Admin via importing a crafted .boardarchive file. Mattermost Advisory ID: MMSA-2026-00672
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 17, 2026Mattermost versions 11.7.x <= 11.7.6, 11.8.x <= 11.8.3 The access control policy unassign endpoint fails to re-validate that each target channel still belongs tCVE-2026-15754 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.2
Mattermost versions 11.7.x <= 11.7.6, 11.8.x <= 11.8.3 The access control policy unassign endpoint fails to re-validate that each target channel still belongs to the requesting admin's team, which allows an authenticated team administrator to remove ABAC (attribute-based access control) policy assignments from channels outside their team via the policy unassign API after a channel has been moved to another team.. Mattermost Advisory ID: MMSA-2026-00718
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 17, 2026Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fails to reconcile SchemeAdmin flags with a user's current role which allows a user CVE-2026-10527 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.3
Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fails to reconcile SchemeAdmin flags with a user's current role which allows a user demoted to System Guest to retain Board Admin privileges and perform admin-only operations via the Boards REST API or UI.. Mattermost Advisory ID: MMSA-2026-00691
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Aug 13, 2026Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to limit decompressed content size and enforce the configuredCVE-2026-14298 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.9.x <= 11.9.0, 11.8.x <= 11.8.4, 11.7.x <= 11.7.7, 10.11.x <= 10.11.22 fail to limit decompressed content size and enforce the configured maximum file size in the Boards archive import handler, which allows an authenticated user to cause memory exhaustion or unbounded disk consumption via a crafted .boardarchive file uploaded to the import endpoint.. Mattermost Advisory ID: MMSA-2026-00713
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 28, 2026Mattermost versions 11.8.x <= 11.8.0, 11.7.x <= 11.7.3, 11.6.x <= 11.6.5, 10.11.x <= 10.11.20 fail to verify file deletion path which allows an admin with SAML CVE-2026-7521 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.5
Mattermost versions 11.8.x <= 11.8.0, 11.7.x <= 11.7.3, 11.6.x <= 11.6.5, 10.11.x <= 10.11.20 fail to verify file deletion path which allows an admin with SAML system-console write permissions to delete arbitrary files outside the config directory from the server via the remove file endpoint.. Mattermost Advisory ID: MMSA-2026-00666
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 27, 2026Mattermost versions 11.6.x <= 11.6.5, 10.11.x <= 10.11.20, 11.8.x <= 11.8.1, 11.7.x <= 11.7.4 fail to limit the number of frames and enforce the file size cap oCVE-2026-10819 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.6.x <= 11.6.5, 10.11.x <= 10.11.20, 11.8.x <= 11.8.1, 11.7.x <= 11.7.4 fail to limit the number of frames and enforce the file size cap on animated GIF uploads, which allows an authenticated attacker to cause a denial of service via a crafted animated GIF uploaded as a custom emoji.. Mattermost Advisory ID: MMSA-2026-00695
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 27, 2026Mattermost versions 11.8.x <= 11.8.0, 11.7.x <= 11.7.3, 11.6.x <= 11.6.5, 10.11.x <= 10.11.20 fail to bound the time and resource consumption of server-side docCVE-2026-10600 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.8.x <= 11.8.0, 11.7.x <= 11.7.3, 11.6.x <= 11.6.5, 10.11.x <= 10.11.20 fail to bound the time and resource consumption of server-side document content extraction which allows an authenticated user with file-upload permission to degrade file uploads for all users on the server via repeatedly uploading small documents that are cheap to upload but expensive to extract, saturating the shared extraction worker pool.. Mattermost Advisory ID: MMSA-2026-00694
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 17, 2026Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious servCVE-2026-9602 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost Desktop App versions <=6.2 6.0.2 5.6.13.0 fail to validate payloads sent from the Mattermost Web App to the Desktop App which allows a malicious server owner to crash the Mattermost Desktop App via changing the payload of a method to a malformed one. Mattermost Advisory ID: MMSA-2026-00678
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 17, 2026Mattermost Desktop App versions <=6.2 5.5.13 6.0.2.0 fail to properly null check when checking for headers in the Mattermost Desktop App which allows any user tCVE-2026-8075 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost Desktop App versions <=6.2 5.5.13 6.0.2.0 fail to properly null check when checking for headers in the Mattermost Desktop App which allows any user to crash another channel members Desktop App via posting a malicious link with an embedded image that misses one of those headers. Mattermost Advisory ID: MMSA-2026-00668
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to check the manage_shared_channels permission in the /share-channel autocompleCVE-2026-9824 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to check the manage_shared_channels permission in the /share-channel autocomplete handler, which allows an authenticated user without that permission to enumerate configured remote cluster connection metadata via slash command autocomplete.. Mattermost Advisory ID: MMSA-2026-00676
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the UserCVE-2026-9820 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.8
Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.1, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to restrict metric configuration changes to the playbook being saved, which allCVE-2026-6541 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.7.x <= 11.7.1, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to restrict metric configuration changes to the playbook being saved, which allows an authenticated user with team access to alter another user’s playbook metric settings via a crafted import or update request with a foreign metric ID. Mattermost Advisory ID: MMSA-2026-00653
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate that an assigned incoming webhook user has access to the target teaCVE-2026-9708 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.9
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate that an assigned incoming webhook user has access to the target team or channel, which allows a requester with webhook management permissions to create posts or direct messages attributed to another user via crafted incoming webhook configuration and payloads.. Mattermost Advisory ID: MMSA-2026-00683
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4 fail to verify whether a guest account is deactivated before creating a session in the magic-link token lCVE-2026-9597 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.4
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4 fail to verify whether a guest account is deactivated before creating a session in the magic-link token login path, which allows a deactivated guest user to obtain a fully functional session via a magic-link token issued prior to deactivation.. Mattermost Advisory ID: MMSA-2026-00681
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to invalidate OAuth refresh tokens upon user account deactivation, which allowsCVE-2026-9571 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.9
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to invalidate OAuth refresh tokens upon user account deactivation, which allows a deactivated user or an attacker in possession of a valid refresh token to obtain new functional access tokens via the OAuth refresh token grant endpoint.. Mattermost Advisory ID: MMSA-2026-00680
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment field values, which alCVE-2026-6850 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to validate the length and content of message attachment field values, which allows an authenticated attacker to cause a denial of service for all users in a channel via a post containing a specially crafted payload that triggers catastrophic backtracking in the client-side markdown parser.. Mattermost Advisory ID: MMSA-2026-00658
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to verify that the channel referenced in an action cookie matches the channel oCVE-2026-10106 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to verify that the channel referenced in an action cookie matches the channel of the target post, which allows an authenticated user without access to a private channel to trigger interactive post actions on posts in that channel via a cookie obtained from any accessible channel.. Mattermost Advisory ID: MMSA-2026-00690
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to verify post ownership in the shared channel inbound sync handler, which alloCVE-2026-10103 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to verify post ownership in the shared channel inbound sync handler, which allows an authenticated remote cluster to modify or delete posts authored by local users or other remotes via crafted sync messages referencing arbitrary post IDs in channels shared with that remote.. Mattermost Advisory ID: MMSA-2026-00689
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 13, 2026Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to restrict the group_constrained channel flag to public and private channels tCVE-2026-10085 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.4
Mattermost versions 11.7.x <= 11.7.2, 11.6.x <= 11.6.4, 10.11.x <= 10.11.19 fail to restrict the group_constrained channel flag to public and private channels that support group synchronization, which allows an ordinary group or direct message member to remove all participants from the conversation via the channel patch API.. Mattermost Advisory ID: MMSA-2026-00688
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 26, 2026Mattermost Plugins versions <=11.6 10.18.11 11.3.6 11.6.5.0 fail to sanitize error responses from the OpenAI API before logging, which allows a user with accessCVE-2026-9699 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.8
Mattermost Plugins versions <=11.6 10.18.11 11.3.6 11.6.5.0 fail to sanitize error responses from the OpenAI API before logging, which allows a user with access to server logs or support packets to obtain a valid or partially reconstructable OpenAI API key via inspection of mattermost.log entries generated during authentication failures. Mattermost Advisory ID: MMSA-2026-00609
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 26, 2026Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 11.5.x <= 11.5.6 fail to validate attachment URLs against internal or private IP ranges in the MatterCVE-2026-4339 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 11.5.x <= 11.5.6 fail to validate attachment URLs against internal or private IP ranges in the Mattermost Agents plugin MCP server which allows an attacker with access to the MCP server in stdio mode to perform server-side request forgery (SSRF) and exfiltrate data from internal network services via supplying internal URLs as file attachments in post creation requests.. Mattermost Advisory ID: MMSA-2026-00635
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 26, 2026Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 11.5.x <= 11.5.6 fail to properly apply markdown image rendering restrictions to AI bot tool result pCVE-2026-3472 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.5
Mattermost versions 10.11.x <= 10.11.18, 11.6.x <= 11.6.3, 11.5.x <= 11.5.6 fail to properly apply markdown image rendering restrictions to AI bot tool result posts, which allows an authenticated attacker to exfiltrate data to an attacker-controlled server via injecting markdown image syntax into tool result content rendered by a victim's client.. Mattermost Advisory ID: MMSA-2026-00619
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 26, 2026The Mattermost Go module github.com/mattermost/mattermost/server/public versions < v0.1.22 fail to validate path parameters when constructing API route paths whCVE-2026-13426 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.4
The Mattermost Go module github.com/mattermost/mattermost/server/public versions < v0.1.22 fail to validate path parameters when constructing API route paths which allows an attacker to redirect API calls to unintended endpoints via crafted IDs containing path traversal components. Mattermost Advisory ID: MMSA-2025-00532
- Product
- github.com/mattermost/mattermost/server/public
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 25, 2026The Mattermost Google Drive plugin before version 1.1.0 fails to validate channel membership in the file creation endpoint, allowing authenticated users with a CVE-2026-2299 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.2
The Mattermost Google Drive plugin before version 1.1.0 fails to validate channel membership in the file creation endpoint, allowing authenticated users with a connected Google account to share Google Drive files to unauthorized private channels and disclose private channel membership.
- Product
- Mattermost Google Drive Plugin
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administratCVE-2026-8823 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.8
Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administrator to degrade arbitrary bot accounts via the standard demote-user API.. Mattermost Advisory ID: MMSA-2026-00669
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to invalidate cached authentication state for active WebSockeCVE-2026-9162 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to invalidate cached authentication state for active WebSocket connections during global session revocation, which allows a user with an existing WebSocket connection to remain authenticated and continue receiving real-time events until the cached session expires or the client reconnects.. Mattermost Advisory ID: MMSA-2026-00664
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to enforce bot-specific permission checks on the user active status endpoint, which allows a UserCVE-2026-8074 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.8
Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to enforce bot-specific permission checks on the user active status endpoint, which allows a User Manager with user management write access but no Integrations access to deactivate bot accounts via the PUT /api/v4/users/{id}/active API endpoint.. Mattermost Advisory ID: MMSA-2026-00667
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to authenticate Atlassian Connect installed callbacks, allowiCVE-2026-6673 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.4
Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to authenticate Atlassian Connect installed callbacks, allowing a remote unauthenticated attacker to inject a rogue sharedSecret and disrupt the Jira integration via POST to /ac/installed during the pending-install window.. Mattermost Advisory ID: MMSA-2026-00654
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 Fail to validate channel ownership of an existing subscription befCVE-2026-6062 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.4
Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 Fail to validate channel ownership of an existing subscription before applying edits which allows an authenticated attacker to hijack subscriptions from channels they have no access to via a crafted PUT request to the subscription edit endpoint.. Mattermost Advisory ID: MMSA-2026-00650
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 22, 2026Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to enforce administrator authorization on the {{setDefaultInsCVE-2026-5139 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.4
Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to enforce administrator authorization on the {{setDefaultInstance}} call within the {{/gitlab connect}} command handler, which allows any authenticated user to overwrite the global default GitLab instance configuration via the {{/gitlab connect <instance-name>}} slash command.. Mattermost Advisory ID: MMSA-2026-00644
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 15, 2026Mattermost Desktop App versions <=6.1 5.5.13.0 fail to account for attempting to open extremely long URLs in the Mattermost Desktop App which allows a maliciousCVE-2026-8683 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost Desktop App versions <=6.1 5.5.13.0 fail to account for attempting to open extremely long URLs in the Mattermost Desktop App which allows a malicious server owner to crash the application via including a script to call window.open on a very large URL. Mattermost Advisory ID: MMSA-2026-00652
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 15, 2026Mattermost Desktop App versions <=6.1 5.5.13.0 fail to restrict the allow list of domains to which NTLM credentials were forwarded to in the Mattermost Desktop CVE-2026-6517 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.3
Mattermost Desktop App versions <=6.1 5.5.13.0 fail to restrict the allow list of domains to which NTLM credentials were forwarded to in the Mattermost Desktop App which allows any user on a server without the image proxy enabled to intercept other users credentials via embedding an image that routes to an external web server. Mattermost Advisory ID: MMSA-2026-00651
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 12, 2026OpenClaw before 2026.5.6 contains an improper access control vulnerability in Mattermost event handlers that fails to validate channel type metadata.CVE-2026-53837 · Other software · OpenClaw · reported by VulnCheckMedium 6.3
OpenClaw before 2026.5.6 contains an improper access control vulnerability in Mattermost event handlers that fails to validate channel type metadata. Attackers can bypass intended DM policy decisions by sending crafted Mattermost events missing channel type information to process restricted content.
- Product
- OpenClaw
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordgithub.comvulncheck.com
Jun 12, 2026Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to require role-management authorization when CVE-2026-7387 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 8.8
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to require role-management authorization when setting the scheme_admin flag on group syncable link and patch endpoints, which allows a user with group-link permissions to escalate themselves and group members to team or channel admin via crafted API requests.. Mattermost Advisory ID: MMSA-2026-00665
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 12, 2026Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15 fail to sanitize the Remote Cluster API response on PATCH operations, which allows aCVE-2026-7184 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15 fail to sanitize the Remote Cluster API response on PATCH operations, which allows authenticated users with the {{manage_secure_connections}} permission to obtain remote cluster authentication tokens via a PATCH request to the remote cluster endpoint.. Mattermost Advisory ID: MMSA-2026-00662
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 12, 2026Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to sanitize FileInfo.Name received from federaCVE-2026-6961 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 7.6
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Mattermost fails to sanitize FileInfo.Name received from federated peers during shared channel file sync, which allows an attacker who controls a federated server to write files to arbitrary locations within the target server's filestore via path traversal sequences in the filename field.. Mattermost Advisory ID: MMSA-2026-00661
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 12, 2026Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to require system-level permission when patching protectedCVE-2026-6739 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.7
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to require system-level permission when patching protected default system roles, which allows authenticated users with delegated user-management permissions to escalate privileges by altering built-in role permissions via the role patch API.. Mattermost Advisory ID: MMSA-2026-00656
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 12, 2026Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Fail to enforce PermissionInviteUser when setting AllowOpenInviCVE-2026-6689 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 Fail to enforce PermissionInviteUser when setting AllowOpenInvite or AllowedDomains during team creation (the check was only applied on update/patch), which allows an authenticated user holding PermissionCreateTeam but not PermissionInviteUser on the resulting team to configure invite-controlled team settings (make the team publicly joinable via open invite and/or constrain membership via allowed domains) that they are not permitted to set on an existing team via POST /api/v4/teams with allow_open_invite: true and/or a non-empty allowed_domains in the request body.. Mattermost Advisory ID: MMSA-2026-00655
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 12, 2026Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to validate that a username returned during bot registratiCVE-2026-6046 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.3
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to validate that a username returned during bot registration belongs to a bot account, which allows an unprivileged attacker to intercept private messages sent by plugins via direct message channels by pre-registering a user account with a predictable plugin bot username.. Mattermost Advisory ID: MMSA-2026-00649
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 12, 2026Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to restrict role_updated websocket event broadcasts to memCVE-2026-3433 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to restrict role_updated websocket event broadcasts to members of the affected team or channel which allows an authenticated attacker with guest-level access to observe permission scheme change notifications for private teams they are not a member of via the websocket connection.. Mattermost Advisory ID: MMSA-2026-00616
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 27, 2026Mattermost Plugins versions <=1.1.5 fail to sanitize filenames received from federated peers before using them to construct export destination paths, which alloCVE-2026-6957 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 8
Mattermost Plugins versions <=1.1.5 fail to sanitize filenames received from federated peers before using them to construct export destination paths, which allows an administrator of a remote federated Mattermost server to write files to arbitrary locations within the target server's filestore via a malicious filename delivered through the shared-channel attachment sync protocol. Mattermost Advisory ID: MMSA-2026-00659
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 25, 2026Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to filter nil elements from outgoing webhook attachment payloCVE-2026-4915 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to filter nil elements from outgoing webhook attachment payloads before processing, which allows an authenticated user to cause a denial of service (server process termination) via a crafted webhook callback response containing a null attachment entry.. Mattermost Advisory ID: MMSA-2026-00641
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 22, 2026Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate the OAuth token scope on the callback which allowCVE-2026-28735 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.4
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate the OAuth token scope on the callback which allows an authenticated Mattermost user to gain access to private repositories via modifying the scope parameter in the GitHub authorization URL.. Mattermost Advisory ID: MMSA-2026-00628
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 22, 2026Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.2, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate the TIFF IFD offset in the imagCVE-2026-5755 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.2, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to validate the TIFF IFD offset in the image header before allocating memory, which allows authenticated users with file upload or posting permissions to cause a denial of service (server OOM) via uploading a crafted TIFF file or posting a URL that serves one.. Mattermost Advisory ID: MMSA-2026-00648
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 22, 2026Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to properly validate msgpack-encoded WebSocket frames before CVE-2026-5740 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 7.5
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to properly validate msgpack-encoded WebSocket frames before memory allocation which allows an unauthenticated remote attacker to crash the server process and cause a full service outage for all users via a crafted binary WebSocket message sent to the public WebSocket endpoint.. Mattermost Advisory ID: MMSA-2026-00647
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Where this comes from: the exploited list is CISA’s Known Exploited Vulnerabilities catalog. Everything else is the whole National Vulnerability Database, where each record is published by the team that found the bug (Wordfence, Patchstack, WPScan, the vendors themselves and others); we show who. Exploit odds are FIRST’s EPSS, updated daily. Titles and categories are ours, so check the linked record before acting on a detail. For a write-up of the big ones, see our advisories. Every vendor, and every WordPress plugin and theme with a recorded flaw, also has its own page. All of it is free to reuse as JSON, CSV or RSS.
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