Vulnerability · Published Jan 16, 2026 · Assigned by Mattermost

CVE-2025-14822DoS from quadratic complexity in model.ParseHashtags

Low 3.1

In plain English

A low-severity security flaw in Mattermost from Mattermost. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 29% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)3.1Low
Exploit odds (30 days)0.3%top 71.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official 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

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Gogithub.com/mattermost/mattermost-server10.11.9GHSA-9r42-rhw3-2222
Gogithub.com/mattermost/mattermost-server11.2.0GHSA-9r42-rhw3-2222
Gogithub.com/mattermost/mattermost-server10.11.9+incompatible, 11.2.0+incompatibleGO-2026-4325

Affected products (as reported)

VendorProductVersions
Mattermost Mattermost 10.11.0 – through 10.11.8

Weakness: CWE-407 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L

References