CVE-2026-6957

MEDIUM EPSS 21.2%

Published May 27, 20261mo ago · Modified Jun 17, 20261w ago

4.9 CVSS 3.1

Medium

Published May 27, 2026 1mo ago

Last Modified Jun 17, 2026 1w ago

Description

Mattermost Plugins versions <=1.1.5 fail to sanitize filenames received from federated peers before using them to construct export destination paths, which allows an administrator of a remote federated Mattermost server to write files to arbitrary locations within the target server's filestore via a malicious filename delivered through the shared-channel attachment sync protocol. Mattermost Advisory ID: MMSA-2026-00659

CVSS Details

Base Score

4.9

Exploitability

1.2

Impact

3.6

Vector string

CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N

Attack Vector Network

Attack Complexity Low

Privileges Required High

User Interaction None

Scope Unchanged

Confidentiality None

Integrity High

Availability None

Threat Intelligence

EPSS Exploit Probability

21.2% percentile

Exploit & Patch Status

No Known Exploit

No Patch Available

Weaknesses 1

CWE-22 Path Traversal Resource Mgmt

Affected Products 1

Vendor	Product	Version	Range
mattermost	legal_hold	*	≤1.1.5

References 1

mattermost.com https://mattermost.com/security-updates

Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.