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.
801 results · page 3 of 17
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.
Jun 9, 2026SQLFluff is a modular SQL linter and auto-formatter with support for multiple dialects and templated code.CVE-2026-46374 · Other software · sqlfluff · reported by GitHubHigh 7.5
SQLFluff is a modular SQL linter and auto-formatter with support for multiple dialects and templated code. Prior to version 4.2.0, in deployments where untrusted users can provide SQL queries to be linted, an untrusted user can submit a malicious long query to any application using the parser to trigger a Denial of Service through resource exhaustion. This issue has been patched in version 4.2.0.
- Product
- sqlfluff
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jun 9, 2026SQLFluff is a modular SQL linter and auto-formatter with support for multiple dialects and templated code.CVE-2026-46373 · Other software · sqlfluff · reported by GitHubHigh 7.5
SQLFluff is a modular SQL linter and auto-formatter with support for multiple dialects and templated code. Prior to version 4.1.0, in deployments where untrusted users can provide SQL queries to be linted, an untrusted user can submit a malicious query with deliberate excessive nesting to any application using the parser to trigger a Denial of Service through resource exhaustion. This issue has been patched in version 4.1.0.
- Product
- sqlfluff
- 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.
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 enforce request body size limits on plugin HTTP endpoints CVE-2026-5308 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.9
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 enforce request body size limits on plugin HTTP endpoints which allows an attacker to cause a denial of service via crafted oversized HTTP requests.. Mattermost Advisory ID: MMSA-2026-00646
- 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 user-supplied input in API request handlers whichCVE-2026-4646 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
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 user-supplied input in API request handlers which allows an authenticated attacker to crash the plugin process via a crafted HTTP request to the PR details endpoint.. Mattermost Advisory ID: MMSA-2026-00638
- 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 archive the channel before removing persistent notificatioCVE-2026-4635 · 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 archive the channel before removing persistent notifications which allows authenticated user to crash the server via timing the creation of persistent notification message between the server deleting existing persistent notifications and archiving the channel.. Mattermost Advisory ID: MMSA-2026-00637
- 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 sanitize team member data when returned via API to users wCVE-2026-3636 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
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 sanitize team member data when returned via API to users without elevated permissions which allows a user without permissions to get data about team members roles via invoking various team API endpoints.. Mattermost Advisory ID: MMSA-2026-00626
- 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 file ownership and access control, which allows aCVE-2026-3473 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 5.9
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 file ownership and access control, which allows an authenticated user to access and download files belonging to other users or teams via crafted Boards API requests using valid file IDs.. Mattermost Advisory ID: MMSA-2026-00620
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 21, 2026In the Drupal 7 Term Reference Tree module, two stored XSS vectors exist in the widget/formatter rendering pipeline.CVE-2026-4093 · Websites & servers · reported by mlhess@drupal.orgMedium 5.1
In the Drupal 7 Term Reference Tree module, two stored XSS vectors exist in the widget/formatter rendering pipeline. Vector A (token display templates): When the Token module is enabled and token display templates are configured, attacker-controlled token output (e.g., term description) is rendered without proper sanitization. Any user who can edit the referenced taxonomy terms can inject HTML/JS that executes when the field is rendered. Vector B (term label rendering): Taxonomy term labels are not properly sanitized before being rendered in the widget, allowing a user with permission to create or edit taxonomy terms to inject scripts into the term name that execute when a form containing the widget is viewed. Exploit affects versions 7.x-1.x up to and including 7.x-1.11.
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordd7es.tag1.comherodevs.com
May 21, 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 check integration URL for path traversal which allows an mCVE-2026-4858 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 8
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 check integration URL for path traversal which allows an malicious authenticated user to call an arbitrary API via system admin Mattermost auth token using via path traversal in integration action URL.. Mattermost Advisory ID: MMSA-2026-00640
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 21, 2026Mattermost Mobile Apps versions <=2.37 11.4 2.0.37 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to properly validate the SSO authentication callback origin which allowsCVE-2026-22880 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.1
Mattermost Mobile Apps versions <=2.37 11.4 2.0.37 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to properly validate the SSO authentication callback origin which allows an attacker controlling a malicious Mattermost server to steal user credentials for a legitimate Mattermost server via relaying the SSO code exchange flow through the mobile application. Mattermost Advisory ID: MMSA-2025-00564
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 21, 2026Mattermost 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 authCVE-2026-4055 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
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 specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields in the Mattermost Calls plugin whichCVE-2026-6347 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 7.6
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields in the Mattermost Calls plugin which allows an attacker with access to a support packet to obtain TURN server credentials via the plaintext values present in the exported plugin configuration.. Mattermost Advisory ID: MMSA-2026-00605
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields before including them in support pacCVE-2026-6346 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 8.7
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields before including them in support packet generation, which allows a Mattermost System Admin or any party with access to a support packet to obtain sensitive credentials in plaintext via downloading a support packet from the System Console.. Mattermost Advisory ID: MMSA-2026-00607
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail prevent disclosure of created user password which allows a malicious attacker tCVE-2026-6345 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail prevent disclosure of created user password which allows a malicious attacker to impersonate a user via the use of some of those passwords.. Mattermost Advisory ID: MMSA-2026-00614
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check public/private permissions which allows members without these permissiCVE-2026-6343 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to check public/private permissions which allows members without these permissions to access public playbooks via /get.. Mattermost Advisory ID: MMSA-2026-00591
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 11.4.x <= 11.4.3 fail to validate the X-Requested-With header on the burn-on-read reveal endpoint which allows an authentiCVE-2026-6339 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.5.x <= 11.5.1, 11.4.x <= 11.4.3 fail to validate the X-Requested-With header on the burn-on-read reveal endpoint which allows an authenticated channel member to force the reveal of a burn-on-read message without recipient consent via a crafted Markdown image tag.. Mattermost Advisory ID: MMSA-2026-00636
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to validate the Host header when constructing response URLs for custom slash commands which allowCVE-2026-6333 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.5
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to validate the Host header when constructing response URLs for custom slash commands which allows an authenticated attacker to redirect slash command responses to an attacker-controlled server via a spoofed Host header.. Mattermost Advisory ID: MMSA-2026-00582
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1 fail to verify channel membership when processing AI-assisted message rewrites which allows an authenticated attacker to reCVE-2026-5163 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost versions 11.5.x <= 11.5.1 fail to verify channel membership when processing AI-assisted message rewrites which allows an authenticated attacker to read the content of threads in private channels and direct messages they do not have access to via a crafted request to the post rewrite endpoint.. Mattermost Advisory ID: MMSA-2026-00645
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent server-rendered content from closing an underlying application view in the Mattermost DesktCVE-2026-4643 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.5
Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent server-rendered content from closing an underlying application view in the Mattermost Desktop App which allows a malicious server or plugin to crash the desktop client via invoking {{window.close()}} in the renderer context, leading to a denial of service condition at the client level. Mattermost Advisory ID: MMSA-2026-00633
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to check if {{team_id}} was being changed when updating playbooks, allowing users with only {{ManCVE-2026-4286 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.1
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to check if {{team_id}} was being changed when updating playbooks, allowing users with only {{Manage Playbook Configurations}} permission to change a playbook's team, bypassing manage members restriction via PUT api. Mattermost Advisory ID: MMSA-2025-00552
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows aCVE-2026-3471 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost Desktop App versions <=6.1 6.0.1 5.4.13.0 fail to prevent an invalid URL from loading in a pop-up window in the Mattermost Desktop App which allows a malicious server owner to repeated crash the application via calling {{window.open('javascript:alert()');}}. Mattermost Advisory ID: MMSA-2026-00618
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to properly check for permissions when processing commands in the Gitlab plugin which allows noCVE-2026-3117 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 6.5
Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to properly check for permissions when processing commands in the Gitlab plugin which allows normal users to uninstall instances or setup webhook connections via the {{gitlab instance {option}}} or the {{/gitlab webhook {option}}} commands. Mattermost Advisory ID: MMSA-2026-00600
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost 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 aCVE-2026-28732 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
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 hijack and impersonate existing system or custom slash commands via editing their own slash command trigger to an already-registered trigger through the command update API. Mattermost Advisory ID: MMSA-2026-00597
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to appropriately check for valid namespaces which allows plugin users to create subscriptions tCVE-2026-6342 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to appropriately check for valid namespaces which allows plugin users to create subscriptions to groups that were not whitelisted via creating groups that share the same prefix as a whitelisted group. Mattermost Advisory ID: MMSA-2026-00601
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to have API-level checks on which groups the user can create issues or attach comments to whichCVE-2026-6341 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost Plugins versions <=11.5 11.1.5 10.13.11 11.3.4.0 fail to have API-level checks on which groups the user can create issues or attach comments to which allows a user that is member of multiple groups to create issues to a locked group via direct API requests. Mattermost Advisory ID: MMSA-2026-00602
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate 7zip archive structure before processing which allows an authenticaCVE-2026-6340 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to validate 7zip archive structure before processing which allows an authenticated attacker to cause server memory exhaustion and denial of service via uploading a specially crafted 7zip file with excessive folder declarations.. Mattermost Advisory ID: MMSA-2026-00573
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
May 18, 2026Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce client identity binding during the OAuth authorization code redemption flow which alloCVE-2026-6334 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.1
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13 fail to enforce client identity binding during the OAuth authorization code redemption flow which allows an authenticated OAuth client to redeem authorization codes issued to a different client via a crafted token exchange request.. Mattermost Advisory ID: MMSA-2026-00570
- 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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