Home/CVE/An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for
CVE

CVE-2018-21256

An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for

An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for group-message channel creation) via the Group message slash command.

MEDIUM · CVSS 4.3 EPSS 0.00152
Monitor
  • No active-exploitation, high-EPSS, or public-exploit signals - routine patching cadence
Sigma rules0 YARA rules0
⬡

Weakness Classification

CWE-732Incorrect Permission Assignment for Critical Resource
▤

Affected Products & Versions

1
mattermost server< 5.1.0
▣

Scoring & Timeline

4.3
MEDIUM · CVSS v3.1 · cve@mitre.org
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD19 Jun 2020 · 06:15 PM
CVSS VectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
🔗

References & Sources

1
Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.
https://mattermost.com/security-updates/Vendor Advisory
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