PT-2026-33036 · Mattermost · Mattermost

Daw10 · Published 2026-04-15 · Updated 2026-04-17 · CVE-2026-27769

Positive Technologies (AI Summary)

CVSS v2.0

4.0

Medium

Base vector

AV:N/AC:L/Au:S/C:N/I:P/A:N

Name of the Vulnerable Software and Affected Versions Mattermost versions 10.11.x through 10.11.12

Description Improper validation of user ownership within the Connected Workspaces feature allows a malicious remote server to change the displayed status of local users via the Connected Workspaces API.

Recommendations Update to a version later than 10.11.12.

Fix

Missing Authorization

Weakness Enumeration

CWE-862

Related Identifiers

BDU:2026-05630

CVE-2026-27769

GHSA-MXXH-FMJQ-J6X4

Affected Products

Mattermost

References · 9

• https://osv.dev/vulnerability/GHSA-mxxh-fmjq-j6x4 · Vendor Advisory
• https://bdu.fstec.ru/vul/2026-05630 · Security Note
• https://mattermost.com/security-updates · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-27769 · Security Note
• https://github.com/mattermost/mattermost · Note
• https://twitter.com/CVEnew/status/2044738006725054536 · Twitter Post
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-27769 · Note
• https://twitter.com/infoflowcloud/status/2044739578372718983 · Twitter Post
• https://twitter.com/VulmonFeeds/status/2044510448024727886 · Twitter Post