Unrated
Denial of service via malformed User-Agent header in getBrowserVersion
CVE-2026-25783
First seen on SecPulse
Original description The description as published by the source.
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to properly validate User-Agent header tokens which allows an authenticated attacker to cause a request panic via a specially crafted User-Agent header. Mattermost Advisory ID: MMSA-2026-00586
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory OSV
References
- advisory github.com
- advisory mattermost.com
- advisory nvd.nist.gov