Vulnerability · Published Mar 16, 2026 · Assigned by Mattermost

CVE-2026-24692Guest users can bypass read permissions via search API

Medium 4.3

In plain English

A medium-severity incorrect authorization in Mattermost from Mattermost. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 7% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)4.3Medium
Exploit odds (30 days)0.2%top 93.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly enforce read permissions in search API endpoints which allows guest users without read permissions to access posts and files in channels via search API requests. Mattermost Advisory ID: MMSA-2025-00554

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/mattermost/mattermost-server11.2.3GHSA-cwfj-642j-gfh4
Gogithub.com/mattermost/mattermost-server5.3.2-0.20260107142155-0481bd1fb045GHSA-cwfj-642j-gfh4
Gogithub.com/mattermost/mattermost-server10.11.11GHSA-cwfj-642j-gfh4
Gogithub.com/mattermost/mattermost-server11.3.1GHSA-cwfj-642j-gfh4
Gogithub.com/mattermost/mattermost-server10.11.11+incompatible, 11.2.3+incompatible, 11.3.1+incompatibleGO-2026-4745
Gogithub.com/mattermost/mattermost-server/v5no fix listedGO-2026-4745
Gogithub.com/mattermost/mattermost-server/v6no fix listedGO-2026-4745
Gogithub.com/mattermost/mattermost/server/v88.0.0-20260107142155-0481bd1fb045GO-2026-4745
Gogithub.com/mattermost/mattermost/server/v88.0.0-20260107142155-0481bd1fb045GHSA-cwfj-642j-gfh4

Affected products (as reported)

VendorProductVersions
Mattermost Mattermost 11.3.0 – through 11.3.011.2.0 – through 11.2.210.11.0 – through 10.11.10

Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N

References