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.
14 results
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.
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.
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 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 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.
Apr 9, 2026Mattermost Plugins versions <=2.1.3.0 fail to limit the request body size on the {{/changes}} webhook endpoint which allows an authenticated attacker to cause mCVE-2026-24661 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.7
Mattermost Plugins versions <=2.1.3.0 fail to limit the request body size on the {{/changes}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Apr 9, 2026Mattermost Plugins versions <=2.3.1 fail to limit the request body size on the {{/lifecycle}} webhook endpoint which allows an authenticated attacker to cause mCVE-2026-21388 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.7
Mattermost Plugins versions <=2.3.1 fail to limit the request body size on the {{/lifecycle}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00610
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 26, 2026Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause servicCVE-2026-3116 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.9
Mattermost Plugins versions <=11.4 11.0.4 11.1.3 11.3.2 10.11.11.0 fail to validate incoming request size which allows an authenticated attacker to cause service disruption via the webhook endpoint. Mattermost Advisory ID: MMSA-2026-00589
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 26, 2026Mattermost Plugins versions <=11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost vCVE-2026-3109 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 2.2
Mattermost Plugins versions <=11.4 10.11.11.0 fail to validate webhook request timestamps which allows an attacker to corrupt Zoom meeting state in Mattermost via replayed webhook requests. Mattermost Advisory ID: MMSA-2026-00584
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 16, 2026Mattermost Plugins versions <=2.0.3.0 fail to properly mask sensitive configuration values which allows an attacker with access to support packets to obtain oriCVE-2026-2476 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comHigh 7.6
Mattermost Plugins versions <=2.0.3.0 fail to properly mask sensitive configuration values which allows an attacker with access to support packets to obtain original plugin settings via exported configuration data. Mattermost Advisory ID: MMSA-2026-00606
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Mar 16, 2026Mattermost Plugins versions <=11.3 11.0.3 11.2.2 10.10.11.0 fail to implement authorisation checks on comment block modifications, which allows an authorised atCVE-2026-2461 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comMedium 4.3
Mattermost Plugins versions <=11.3 11.0.3 11.2.2 10.10.11.0 fail to implement authorisation checks on comment block modifications, which allows an authorised attacker with editor permission to modify comments created by other board members. Mattermost Advisory ID: MMSA-2025-00559
- Product
- Mattermost
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Jul 17, 2023Mattermost WelcomeBot plugin fails to to validate the membership status when inviting or adding users to channels allowing guest accounts to be added or invitedCVE-2023-3613 · Other software · Mattermost · reported by responsibledisclosure@mattermost.comLow 3.5
Mattermost WelcomeBot plugin fails to to validate the membership status when inviting or adding users to channels allowing guest accounts to be added or invited to channels by default.
- Product
- Mattermost Plugins
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordmattermost.commattermost.com
Jun 19, 2020An issue was discovered in Mattermost Plugins before 5.13.0.CVE-2019-20864 · Other software · Mattermost · reported by MITREHigh 7.5
An issue was discovered in Mattermost Plugins before 5.13.0. The GitHub plugin allows an attacker to attach his Mattermost account to a different person's GitHub account.
- Product
- Mattermost Plugins
- What to do
- Apply the vendor’s update. The NVD record links to the advisory.
Full record and what to do →NVD recordmattermost.commattermost.com
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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