CVE-2025-12421 is a critical authentication bypass vulnerability affecting Mattermost versions 11.0.2 and earlier, 10.12.1 and earlier, 10.11.4 and earlier, and 10.5.12 and earlier. It allows an authenticated user to perform account takeover by exploiting a flaw in the code exchange process when switching authentication methods, provided ExperimentalEnableAuthenticationTransfer is enabled and RequireEmailVerification is disabled. Rated 9.9 CRITICAL (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H), this vulnerability has a low attack complexity and can lead to complete compromise of confidentiality, integrity, and availability. There is currently no public exploit code available, no evidence of active exploitation, and minimal community discussion surrounding this CVE.
| Vendor | Product | Version(s) | CPE |
|---|---|---|---|
>= 10.5.0, < 10.5.13CPE matchmatch criteria | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | ||
>= 10.11.0, < 10.11.5CPE matchmatch criteria | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | ||
>= 10.12.0, < 10.12.2CPE matchmatch criteria | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | ||
>= 11.0.0, < 11.0.3CPE matchmatch criteria | cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:* | ||
>= 10.11.0, <= 10.11.4CPE match | cpe:2.3:a:mattermost:mattermost:*:*:*:*:*:*:*:* |
CVSS version used by this source: 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 1.0 Bluesky, 0.5 Mastodon, and 1.6 GitHub mentions.
No media coverage found for this CVE.
The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.