Vulnerability DatabaseCVE-2026-4858
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CVE-2026-4858
Published:May 21, 2026
Updated:June 11, 2026
Mattermost versions 11.6.x <= 11.6.0, 11.5.x <= 11.5.3, 11.4.x <= 11.4.4, 10.11.x <= 10.11.14 fail to check integration URL for path traversal which allows an malicious authenticated user to call an arbitrary API via system admin Mattermost auth token using via path traversal in integration action URL.. Mattermost Advisory ID: MMSA-2026-00640
Affected Packages
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.4.0 <v11.4.5
Fix Suggestion:
Update to version v11.4.5
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v11.5.0 <v11.5.4
Fix Suggestion:
Update to version v11.5.4
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) =v11.6.0 <v11.6.1
Fix Suggestion:
Update to version v11.6.1
https://github.com/mattermost/mattermost.git (GITHUB):
Affected version(s) >=v10.11.0 <v10.11.15
Fix Suggestion:
Update to version v10.11.15
github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.5.0 <v11.5.4
Fix Suggestion:
Update to version v11.5.4
github.com/mattermost/mattermost (GO):
Affected version(s) >=v11.4.0 <v11.4.5
Fix Suggestion:
Update to version v11.4.5
github.com/mattermost/mattermost (GO):
Affected version(s) >=v10.11.0 <v10.11.15
Fix Suggestion:
Update to version v10.11.15
github.com/mattermost/mattermost (GO):
Affected version(s) =v11.6.0 <v11.6.1
Fix Suggestion:
Update to version v11.6.1
Related Resources (1)
https://mattermost.com/security-updates
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CVSS v4
Base Score:
8.9
Attack Vector
NETWORK
Attack Complexity
HIGH
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
PASSIVE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
HIGH
Subsequent System Integrity
HIGH
Subsequent System Availability
HIGH
CVSS v3
Base Score:
8
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH
Weakness Type (CWE)
Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CWE-22
EPSS
Base Score:
0.05