Description
Mattermost versions 10.11.x <= 10.11.8 fail to validate input size before processing hashtags which allows an authenticated attacker to exhaust CPU resources via a single HTTP request containing a post with thousands space-separated tokens
References (1)
Scores
CVSS v3
3.1
EPSS
0.0002
EPSS Percentile
5.8%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-770
CWE-407
Status
published
Products (2)
mattermost/mattermost-server
10.11.0 - 10.11.9Go
mattermost/mattermost_server
10.11.0 - 10.11.9
Published
Jan 16, 2026
Tracked Since
Feb 18, 2026