CVE-2026-18551

Mattermost versions 11.10.x = 11.10.0, 11.7.x = 11.7.9, 11.9.x = 11.9.1, 11.8.x = 11.8.5 fail to validate the combination of guest and admin scheme roles which allows an authenticated attacker to escalate a guest account to team or channel admin via a crafted PUT request to the member roles API...

CVE-2026-18551 Mattermost guest account privilege escalation via member roles API

Mattermost versions 11.10.x = 11.10.0, 11.7.x = 11.7.9, 11.9.x = 11.9.1, 11.8.x = 11.8.5 fail to validate the combination of guest and admin scheme roles which allows an authenticated attacker to escalate a guest account to team or channel admin via a crafted PUT request to the member roles API...

CVE-2026-18551

Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, and 11.8.x

CVE-2026-18551 Mattermost guest account privilege escalation via member roles API

Mattermost versions 11.10.x = 11.10.0, 11.7.x = 11.7.9, 11.9.x = 11.9.1, 11.8.x = 11.8.5 fail to validate the combination of guest and admin scheme roles which allows an authenticated attacker to escalate a guest account to team or channel admin via a crafted PUT request to the member roles API...

EUVD-2026-102806

Mattermost versions 11.10.x = 11.10.0, 11.7.x = 11.7.9, 11.9.x = 11.9.1, 11.8.x = 11.8.5 fail to validate the combination of guest and admin scheme roles which allows an authenticated attacker to escalate a guest account to team or channel admin via a crafted PUT request to the member roles API...

PT-2026-115509

Name of the Vulnerable Software and Affected Versions Mattermost version 11.10.0 Mattermost version 11.7.9 Mattermost version 11.9.1 Mattermost version 11.8.5 Description An issue exists where the system fails to validate the combination of guest and admin scheme roles. This allows an authenticat...

CVE-2026-18551: Incorrect Authorization

Mattermost versions 11.10.x = 11.10.0, 11.7.x = 11.7.9, 11.9.x = 11.9.1, 11.8.x = 11.8.5 fail to validate the combination of guest and admin scheme roles which allows an authenticated attacker to escalate a guest account to team or channel admin via a crafted PUT request to the member roles API...

CVE-2026-9816

Mattermost 11.7.x (≤11.7.6), 10.11.x (≤10.11.21), and 11.8.x (≤11.8.3) lack server-side validation of BoardMember.Scheme* fields on insert and archive-import paths, allowing board editors or non-guest team members to grant Board Admin to arbitrary users via POST /api/v2/boards/{boardID}/members a...

CVE-2026-16048

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...

CVE-2026-16048 Channel member roles accept out-of-scope roles

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...

CVE-2026-16048

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...

CVE-2026-16048: Incorrect Authorization

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...

PT-2026-76662

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...

CVE-2026-63101

Open Event Server through 1.19.1 contains a missing authentication vulnerability that allows unauthenticated attackers to export the complete member roster of any group, including email addresses, names, join dates, and roles, by submitting requests to the group followers CSV export endpoint whic...

CVE-2026-59258

immich before 3.0.3 contains a broken access control vulnerability in the PUT /albums/:id/user/:userId endpoint that allows shared album editors to modify member roles without owner-only restrictions. Attackers with editor access can demote the album owner to editor and promote themselves to owne...

CVE-2026-59258

CVE-2026-59258 affects Immich before 3.0.3. A broken access control on PUT /albums/:id/user/:userId lets shared album editors modify member roles, enabling an editor to demote the owner to editor and promote themselves to owner via sequential requests, yielding full control including deletion and...

PT-2026-51223

Name of the Vulnerable Software and Affected Versions Capgo versions prior to 12.128.2 Description Improper access control in the public.get org members RPC function allows unauthenticated attackers to enumerate organization members. By using a public sb publishable key and an organization UUID,...

CVE-2026-39374

Plane is an an open-source project management tool. Prior to 1.3.0, the IssueBulkUpdateDateEndpoint allows a project member ADMIN or MEMBER to modify the startdate and targetdate of ANY issue across the entire Plane instance, regardless of workspace or project membership. The endpoint fetches...

PraisonAI has Cross-Workspace IDOR and Privilege Escalation via Platform API

Summary The PraisonAI Platform API has two authorization failures that together break workspace isolation. The service layer for issues and projects performs global primary-key lookups without checking workspace ownership, so any authenticated user can read, modify, and delete resources in any...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via the API response process. An attacker can access sensitive information about team member roles by invoking various team API endpoints without having elevated permissions. Remediation Upgrade...