CVE-2026-9693

Mattermost versions 10.11.x = 10.11.20, 11.7.x = 11.7.5 Mattermost fails to remove thread membership records when a user is removed from or leaves a team, which allows a previously removed user who is later re-invited to the team to view private channel thread root post content and metadata via t...

CVE-2026-9693

Mattermost 10.11.x (≤10.11.20) and 11.7.x (≤11.7.5) fail to delete thread membership records when a user leaves or is removed from a team. A previously removed user who is later re-invited can access private channel thread root post content and metadata via the team threads API, causing low confi...

CVE-2026-59714

Open WebUI is an extensible, feature-rich, and user-friendly self-hosted AI platform. From 0.9.5 before 0.10.0, any authenticated user can overwrite the content of a message in a channel they do not belong to including private and DM channels by sending a chat completion request with a...

CVE-2026-48078

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 1.0.5, the unauthenticated /api/tenants/id/schedule endpoint returns every non-archived channel for a tenant regardless of the channel's isPublic flag. Channels marked...

CVE-2026-48078 OpenReception's schedule endpoint discloses isPublic=false channels and slot availability to unauthenticated callers

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 1.0.5, the unauthenticated /api/tenants/id/schedule endpoint returns every non-archived channel for a tenant regardless of the channel's isPublic flag. Channels marked...

CVE-2026-48078

OpenReception’s CVE-2026-48078 affects the scheduling endpoint prior to version 1.0.5. The unauthenticated /api/tenants/{id}/schedule endpoint exposed all non-archived channels for a tenant, including those with isPublic = false, disclosing channel names, descriptions, IDs, agent associations, pa...

EUVD-2026-54148

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. Prior to version 1.0.5, the unauthenticated /api/tenants/id/schedule endpoint returns every non-archived channel for a tenant regardless of the channel's isPublic flag. Channels marked...

CVE-2026-48076 OpenReception's bootstrap booking flow allows unauthenticated booking on isPublic=false channels

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. The new-client booking flow in versions 1.0.1 and prior consists of three calls: bootstrap-challenge returns a 16-bit PoW challenge with difficulty=4 leading hex zeroes, bootstrap-verify...

CVE-2026-48076 OpenReception's bootstrap booking flow allows unauthenticated booking on isPublic=false channels

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. The new-client booking flow in versions 1.0.1 and prior consists of three calls: bootstrap-challenge returns a 16-bit PoW challenge with difficulty=4 leading hex zeroes, bootstrap-verify...

EUVD-2026-54145

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. The new-client booking flow in versions 1.0.1 and prior consists of three calls: bootstrap-challenge returns a 16-bit PoW challenge with difficulty=4 leading hex zeroes, bootstrap-verify...

CVE-2026-48076

OpenReception’s bootstrap booking flow (versions ≤1.0.1) is vulnerable to an unauthenticated booking against private channels due to a missing channel binding in the booking token. The 3-step flow: bootstrap-challenge (PoW), bootstrap-verify (issues a booking access token), and create-new-client ...

CVE-2026-48076 OpenReception's bootstrap booking flow allows unauthenticated booking on isPublic=false channels

OpenReception's appointment booking software provides an end-to-end encrypted appointment booking platform. The new-client booking flow in versions 1.0.1 and prior consists of three calls: bootstrap-challenge returns a 16-bit PoW challenge with difficulty=4 leading hex zeroes, bootstrap-verify...

SUSE CVE-2026-5163

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...

SUSE CVE-2026-28759

Mattermost versions 11.5.x = 11.5.1, 10.11.x = 10.11.13, 11.4.x = 11.4.3 fail to validate that a remote cluster has access to a channel before processing membership removal requests during shared channel membership sync, which allows a malicious remote cluster to remove any user from any channel,...

Open WebUI Missing Access Check on Channel Members Endpoint for Standard Channels

Missing Access Check on Channel Members Endpoint for Standard Channels Affected ComponentChannel members listing endpoint:- backend/openwebui/routers/channels.py lines 445-507, getchannelmembersbyid Affected VersionsCurrent main branch and likely all versions with the channels feature...

Incorrect Authorization

Overview github.com/mattermost/mattermost/server/v8/channels/api4 is a platform for secure collaboration across the entire software development lifecycle Affected versions of this package are vulnerable to Incorrect Authorization via a mismatch between the channel referenced in an action cookie a...

Incorrect Authorization

Overview Affected versions of this package are vulnerable to Incorrect Authorization via a mismatch between the channel referenced in an action cookie and the channel of the target post. An attacker can perform unauthorized interactive post actions in private channels by using a cookie obtained...

CVE-2026-10106 Unauthorized users can trigger interactive post actions in private channels via action cookie channel mismatch in Mattermost

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 th...

CVE-2026-10106 Unauthorized users can trigger interactive post actions in private channels via action cookie channel mismatch in Mattermost

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 th...

PT-2026-57653

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...