CVE-2026-28741
published 2026-04-15CVE-2026-28741: Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which…
PriorityP345high8.1CVSS 3.1
AVNACLPRNUIRSUCHIHAN
EPSS
0.13%
3.0th percentile
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which allows an attacker to update a user's authentication method via a CSRF attack by tricking a user into visiting a malicious page. Mattermost Advisory ID: MMSA-2026-00625
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github.com | mattermost_mattermost_server_v8 | >= 11.3.0-rc1 < 11.3.3 | 11.3.3 |
| github.com | mattermost_mattermost_server_v8 | >= 11.4.0-rc1 < 11.4.3 | 11.4.3 |
| github.com | mattermost_mattermost_server_v8 | >= 11.5.0-rc1 < 11.5.0 | 11.5.0 |
| github.com | mattermost_mattermost_server_v8 | >= 8.0.0-20250721062209-4952acea88ce < 8.0.0-20260220133927-c29cf05d40f8 | 8.0.0-20260220133927-c29cf05d40f8 |
| mattermost | mattermost | 10.11.0 – 10.11.12 | — |
| mattermost | mattermost | 11.3.0 – 11.3.2 | — |
| mattermost | mattermost | 11.4.0 – 11.4.2 | — |
| mattermost | mattermost | 11.5.0 – 11.5.0 | — |
| mattermost | mattermost_server | >= 10.11.0 < 10.11.13 | 10.11.13 |
| mattermost | mattermost_server | >= 11.3.0 < 11.3.3 | 11.3.3 |
| mattermost | mattermost_server | >= 11.4.0 < 11.4.3 | 11.4.3 |
| mattermost | mattermost_server | >= 11.5.0 < 11.5.1 | 11.5.1 |
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GHSA
Mattermost doesn't validate CSRF tokens on an authentication endpoint
ghsa·2026-04-17
CVE-2026-28741 [MEDIUM] CWE-352 Mattermost doesn't validate CSRF tokens on an authentication endpoint
Mattermost doesn't validate CSRF tokens on an authentication endpoint
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which allows an attacker to update a user's authentication method via a CSRF attack by tricking a user into visiting a malicious page. Mattermost Advisory ID: MMSA-2026-00625.
GHSA
GHSA-m7cf-4gh2-v4qg: Mattermost versions 10
ghsa_unreviewed·2026-04-17
CVE-2026-28741 [MEDIUM] CWE-352 GHSA-m7cf-4gh2-v4qg: Mattermost versions 10
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which allows an attacker to update a user's authentication method via a CSRF attack by tricking a user into visiting a malicious page. Mattermost Advisory ID: MMSA-2026-00625
VulDB
Mattermost up to 10.11.12/11.3.2/11.4.2/11.5.0 cross-site request forgery
vuldb·2026-04-15·CVSS 6.8
CVE-2026-28741 [MEDIUM] Mattermost up to 10.11.12/11.3.2/11.4.2/11.5.0 cross-site request forgery
A vulnerability, which was classified as problematic, has been found in Mattermost up to 10.11.12/11.3.2/11.4.2/11.5.0. The affected element is an unknown function. This manipulation causes cross-site request forgery.
This vulnerability is registered as CVE-2026-28741. Remote exploitation of the attack is possible. No exploit is available.
It is advisable to upgrade the affected component.
No detection rules found.
No public exploits indexed.
Bugzilla
CVE-2026-28741 mattermost: CSRF protection bypass allows updating a user's authentication method
bugzilla·2026-04-15·CVSS 6.8
CVE-2026-28741 [MEDIUM] CVE-2026-28741 mattermost: CSRF protection bypass allows updating a user's authentication method
CVE-2026-28741 mattermost: CSRF protection bypass allows updating a user's authentication method
Mattermost versions 10.11.x <= 10.11.12, 11.5.x <= 11.5.0, 11.4.x <= 11.4.2, 11.3.x <= 11.3.2 fail to validate CSRF tokens on an authentication endpoint which allows an attacker to update a user's authentication method via a CSRF attack by tricking a user into visiting a malicious page. Mattermost Advisory ID: MMSA-2026-00625
Bugzilla
CVE-2026-28741 matterbridge: CSRF protection bypass allows updating a user's authentication method [fedora-all]
bugzilla·2026-04-15·CVSS 6.8
CVE-2026-28741 [MEDIUM] CVE-2026-28741 matterbridge: CSRF protection bypass allows updating a user's authentication method [fedora-all]
CVE-2026-28741 matterbridge: CSRF protection bypass allows updating a user's authentication method [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Bugzilla
CVE-2026-28741 matterbridge: CSRF protection bypass allows updating a user's authentication method [epel-all]
bugzilla·2026-04-15·CVSS 6.8
CVE-2026-28741 [MEDIUM] CVE-2026-28741 matterbridge: CSRF protection bypass allows updating a user's authentication method [epel-all]
CVE-2026-28741 matterbridge: CSRF protection bypass allows updating a user's authentication method [epel-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
2026-04-15
Published