CVE-2026-28741

medium

Published 2026-04-17 · Modified 2026-04-29

💬 Discuss on Community ✚ Propose mitigation

CVSS v3

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CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N

CVSS v4 NEW

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not yet in upstream

VIR risk

5.5

Description

Mattermost doesn't validate CSRF tokens on an authentication endpoint

Predictions

Exploit likelihood

30%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Package impact

Ecosystem	Package	Vulnerable	Fixed
Go	github.com/mattermost/mattermost/server/v8	`>=8.0.0-20250721062209-4952acea88ce,<8.0.0-20260220133927-c29cf05d40f8`	`8.0.0-20260220133927-c29cf05d40f8`
Go	github.com/mattermost/mattermost/server/v8	`>=11.5.0-rc1,<11.5.0`	`11.5.0`
Go	github.com/mattermost/mattermost/server/v8	`>=11.4.0-rc1,<11.4.3`	`11.4.3`
Go	github.com/mattermost/mattermost/server/v8	`>=11.3.0-rc1,<11.3.3`	`11.3.3`
GO	github.com/mattermost/mattermost/server/v8	`>= 11.3.0-rc1, < 11.3.3`	`11.3.3`
GO	github.com/mattermost/mattermost/server/v8	`>= 11.4.0-rc1, < 11.4.3`	`11.4.3`
GO	github.com/mattermost/mattermost/server/v8	`= 11.5.0-rc1`	`11.5.0`
GO	github.com/mattermost/mattermost/server/v8	`>= 8.0.0-20250721062209-4952acea88ce, < 8.0.0-20260220133927-c29cf05d40f8`	`8.0.0-20260220133927-c29cf05d40f8`

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.