CVE-2021-37862 Business logic in Mattermost
Attackers can trick users into signing up with attacker-controlled emails via crafted invitation tokens, potentially leading to account takeover.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-37862?
CVE-2021-37862 is a low-severity vulnerability in Mattermost Mattermost Server, published on 17 Dec 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Mattermost 6.0 and earlier fails to sufficiently validate the email address during registration, which allows attackers to trick users into signing up using attacker-controlled email addresses via crafted invitation token.
Weakness: CWE-754
Which versions are affected by CVE-2021-37862?
1 open source package ship an affected version, including mattermost. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mattermost Bitnami | All versions | 6.0.1 |
Products include Mattermost Mattermost Server.
How do I fix CVE-2021-37862?
Upgrade mattermost to 6.0.1 or later.
Is CVE-2021-37862 being exploited?
There is no known exploitation of CVE-2021-37862 in the wild and no public exploit code.
Other vulnerabilities in Mattermost Mattermost Server
- CVE-2025-12419 Account takeover on OAuth/OpenID-enabled servers
- CVE-2025-12421 Account Takeover via Code Exchange Endpoint
- CVE-2025-4981 Path Traversal Leading to RCE by Any Authenticated Mattermost User
- CVE-2025-20051 Arbitrary file read via block duplication in Mattermost Boards
- CVE-2025-25279 Arbitrary file read in Mattermost Boards via import & export board archive
Sources
Also known as BIT-mattermost-2021-37862, GHSA-5ffg-379q-g96f.