CVE-2020-14459 Business logic in n/a
Attackers can rename channels to collide with direct messages, potentially disrupting communication integrity in Mattermost Server.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2020-14459?
CVE-2020-14459 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, with no action from the victim.
Official description
An issue was discovered in Mattermost Server before 5.19.0. Attackers can rename a channel and cause a collision with a direct message, aka MMSA-2020-0002.
Weakness: CWE-20
Which versions are affected by CVE-2020-14459?
1 open source package ship an affected version, including mattermost. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
mattermost Bitnami | All versions | 5.19.0 |
Products include Mattermost Mattermost Server.
How do I fix CVE-2020-14459?
Upgrade mattermost to 5.19.0 or later.
Is CVE-2020-14459 being exploited?
There is no known exploitation of CVE-2020-14459 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-2020-14459, GHSA-2g33-mqvh-5w7c.