CVE-2025-14822

DoS from quadratic complexity in model.ParseHashtags

Published Jan 16, 2026 CVSS 3.1 · 3.1 Low EPSS < 1% KEV · Not listed
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

Remediation

Vendor Solution

Update Mattermost to versions 11.2.0, 10.11.9 or higher.

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-9r42-rhw3-2222 Mattermost is vulnerable to CPU exhaustion via crafted HTTP request
References
History
Type Values Removed Values Added
First Time appeared Mattermost mattermost Server
Weaknesses CWE-770
CPEs cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*
Vendors & Products Mattermost mattermost Server
Type Values Removed Values Added
First Time appeared Mattermost
Mattermost mattermost
Vendors & Products Mattermost
Mattermost mattermost
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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
Title DoS from quadratic complexity in model.ParseHashtags
Weaknesses CWE-407
References
Metrics cvssV3_1

{'score': 3.1, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
Mattermost
Published
Updated
Jan 16, 2026, 1:00 PM
Reserved
Dec 17, 2025, 11:54 AM
Status
Analyzed
Published
Jan 16, 2026, 9:16 AM
Modified
Jun 17, 2026, 8:36 AM