CVE-2026-6957

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Source

https://cve.org/CVERecord?id=CVE-2026-6957

Import Source

https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-6957.json

JSON Data

https://api.osv.dev/v1/vulns/CVE-2026-6957

Published

2026-05-27T14:23:50.770Z

Modified

2026-07-08T08:14:23.960003467Z

Severity

8.0 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H CVSS Calculator

Summary

Path traversal in Mattermost Legal Hold plugin via unsanitized file name from federated peer allows arbitrary file write.

Details

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

Database specific

{
    "unresolved_ranges": [
        {
            "source": "AFFECTED_FIELD",
            "extracted_events": [
                {
                    "last_affected": "1.1.5"
                }
            ]
        }
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/6xxx/CVE-2026-6957.json",
    "cna_assigner": "Mattermost",
    "cwe_ids": [
        "CWE-22"
    ]
}

References

Affected packages

Git / github.com/mattermost/mattermost-plugin-legal-hold

Affected ranges

Type

GIT

Repo

https://github.com/mattermost/mattermost-plugin-legal-hold

Events

Introduced

Last affected

8c830da21205c49d78929e1151384ccb10e14d97

Database specific

{
    "source": "CPE_RANGE",
    "cpe": "cpe:2.3:a:mattermost:legal_hold:*:*:*:*:*:mattermost:*:*",
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "last_affected": "1.1.5"
        }
    ]
}

Affected versions

1.*

1.1.5

v0.*

v0.1.0

v0.2.0

v0.3.0

v0.3.1

v0.3.2

v0.3.3

v0.3.4

v0.4.0

v0.4.1

v0.4.2

v0.4.3

v0.5.0-rc1

v1.*

v1.0.0

v1.0.1

v1.0.2

v1.1.0

v1.1.0-rc1

v1.1.1

v1.1.2

v1.1.3

v1.1.4

v1.1.5

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-6957.json"