GitHub Advisoryadvisory · Go

GHSA-ph22-fw5m-w2q9 Mattermost allows attackers to spoof permalink embeds

MEDIUM Published 2026-03-16 Modified 2026-03-17 Official page ↗
Aliases
CVE-2026-2457
Ecosystem
Go
Packages
github.com/mattermost/mattermost/server/v8, github.com/mattermost/mattermost-server
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Weaknesses
CWE-346
Reviewed
2026-03-17

Affected packages

• Go github.com/mattermost/mattermost/server/v8: < 8.0.0-20260123211116-9efe617be8b8 → fixed in 8.0.0-20260123211116-9efe617be8b8 • Go github.com/mattermost/mattermost-server: < 5.3.2-0.20260123211116-9efe617be8b8 → fixed in 5.3.2-0.20260123211116-9efe617be8b8 • Go github.com/mattermost/mattermost-server: >= 10.11.0-rc1, < 10.11.11 → fixed in 10.11.11 • Go github.com/mattermost/mattermost-server: >= 11.2.0-rc1, < 11.2.3 → fixed in 11.2.3 • Go github.com/mattermost/mattermost-server: >= 11.3.0-rc1, < 11.3.1 → fixed in 11.3.1

Description

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to sanitize client-supplied post metadata which allows an authenticated attacker to spoof permalink embeds impersonating other users via crafted PUT requests to the post update API endpoint. Mattermost Advisory ID: MMSA-2025-00569

Related

Alias · CVE (1)

  • CVE-2026-2457 Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to sanitize client-supplied post metadata which allows an… vulnerability

Weakness · CWE (1)

  • CWE-346 Origin Validation Error weakness

References