CVE-2025-55035: mattermost
Vulnerability summary
CVE-2025-55035 is a medium (CVSS 6.1) vulnerability in mattermost. EPSS estimates a 0.32% chance of exploitation in the next 30 days, higher than 23% of scored vulnerabilities.
Timeline
- 16-10-2025PublishedVulnerability first disclosed.
- 16-10-2025Last modifiedVulnerability information updated.
Description
Mattermost Desktop App versions <=5.13.0 fail to manage modals in the Mattermost Desktop App that stops a user with a server that uses basic authentication from accessing their server which allows an attacker that provides a malicious server to the user to deny use of the Desktop App via having the user configure the malicious server and forcing a modal popup that cannot be closed.
CVSS metrics
2 scores · 2 sources · 1 version- NVDNIST6.1MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:N/A:H
EPSS trend
Probability
0.32%
Chance of exploitation in the next 30 days
Percentile
23%
Versus all other CVEs
30-day change
0.00 pp
From 0.32% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Mattermost2 products
- mattermost≤ 5.0.13
- mattermost_desktop< 5.13.1.0
1 vendor · 2 products
References
1 links- mattermost.com/security-updatesVendor Advisory