CVE-2019-20865 Cross-site request forgery in n/a
Attackers can perform unauthorized actions on behalf of authenticated users via CSRF on the login page, requiring an upgrade to Mattermost Server.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2019-20865?
CVE-2019-20865 is a high-severity vulnerability in Mattermost Mattermost Server, published on 19 Jun 2020. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
An issue was discovered in Mattermost Server before 5.12.0, 5.11.1, 5.10.2, 5.9.2, and 4.10.10. The login page allows CSRF.
Weakness: CWE-352
Which versions are affected by CVE-2019-20865?
It affects 1 product.
Products include Mattermost Mattermost Server.
How do I fix CVE-2019-20865?
No fix has been published for CVE-2019-20865 yet. Limit exposure of the affected software until one is available.
Is CVE-2019-20865 being exploited?
There is no known exploitation of CVE-2019-20865 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 GHSA-c22c-gjcp-pjjp.