Vulnerability-Lookup

GHSA-9P64-JPC7-M2RP

Vulnerability from github – Published: 2026-05-18 09:31 – Updated: 2026-06-01 15:41

Summary

Mattermost doesn't sanitize sensitive configuration fields before including them in support packet generation

Details

Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 fail to sanitize sensitive configuration fields before including them in support packet generation, which allows a Mattermost System Admin or any party with access to a support packet to obtain sensitive credentials in plaintext via downloading a support packet from the System Console.. Mattermost Advisory ID: MMSA-2026-00607

Severity

8.7 (High)


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

Show details on source website

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/mattermost/mattermost/server/v8"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "11.5.0"
            },
            {
              "fixed": "11.5.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/mattermost/mattermost/server/v8"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.11.0"
            },
            {
              "fixed": "10.11.14"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/mattermost/mattermost/server/v8"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "11.4.0"
            },
            {
              "fixed": "11.4.4"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/mattermost/mattermost/server/v8"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "8.0.0-20260326202606-fac92f4a71f3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Go",
        "name": "github.com/mattermost/mattermost-server"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5.3.2-0.20260326202606-fac92f4a71f3"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-6346"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-200"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-06-01T15:41:08Z",
    "nvd_published_at": "2026-05-18T09:16:24Z",
    "severity": "HIGH"
  },
  "details": "Mattermost versions 11.5.x \u003c= 11.5.1, 10.11.x \u003c= 10.11.13, 11.4.x \u003c= 11.4.3 fail to sanitize sensitive configuration fields before including them in support packet generation, which allows a Mattermost System Admin or any party with access to a support packet to obtain sensitive credentials in plaintext via downloading a support packet from the System Console.. Mattermost Advisory ID: MMSA-2026-00607",
  "id": "GHSA-9p64-jpc7-m2rp",
  "modified": "2026-06-01T15:41:08Z",
  "published": "2026-05-18T09:31:48Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-6346"
    },
    {
      "type": "WEB",
      "url": "https://github.com/mattermost/mattermost/commit/fac92f4a71f356009e27983a980f729f599e8ba5"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/mattermost/mattermost"
    },
    {
      "type": "WEB",
      "url": "https://mattermost.com/security-updates"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Mattermost doesn\u0027t sanitize sensitive configuration fields before including them in support packet generation"
}

CVE-2026-6346 (GCVE-0-2026-6346)

Vulnerability from cvelistv5 – Published: 2026-05-18 08:37 – Updated: 2026-05-18 14:37

Title

Sensitive credentials exposed in plaintext in Mattermost support packets

Summary

Severity

8.7 (High)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-18 14:37 UTC

CWE

CWE-200 - Exposure of Sensitive Information to an Unauthorized Actor

Assigner

Mattermost mitre root

References

1 reference

URL	Tags
https://mattermost.com/security-updates	vendor-advisory

Impacted products

1 product

Vendor	Product	Version
Mattermost	Mattermost	Affected: 11.5.0 , ≤ 11.5.1 (semver) Affected: 10.11.0 , ≤ 10.11.13 (semver) Affected: 11.4.0 , ≤ 11.4.3 (semver) Unaffected: 11.6.0 Unaffected: 11.5.2 Unaffected: 10.11.14 Unaffected: 11.4.4

Credits

Edgar Bellot Micó

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-6346",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-18T14:37:05.559827Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-05-18T14:37:17.045Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
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              "lessThanOrEqual": "11.5.1",
              "status": "affected",
              "version": "11.5.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "10.11.13",
              "status": "affected",
              "version": "10.11.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "11.4.3",
              "status": "affected",
              "version": "11.4.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "11.6.0"
            },
            {
              "status": "unaffected",
              "version": "11.5.2"
            },
            {
              "status": "unaffected",
              "version": "10.11.14"
            },
            {
              "status": "unaffected",
              "version": "11.4.4"
            }
          ]
        }
      ],
      "credits": [
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          "type": "finder",
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        }
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          "lang": "en",
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        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 8.7,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "HIGH",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
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      "providerMetadata": {
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      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost to versions 11.6.0, 11.5.2, 10.11.14, 11.4.4 or higher."
        }
      ],
      "source": {
        "advisory": "MMSA-2026-00607",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-67535"
        ],
        "discovery": "{\"self\"=\u003e\"https://mattermost.atlassian.net/rest/api/2/customFieldOption/10557\", \"value\"=\u003e\"Internal\", \"id\"=\u003e\"10557\"}"
      },
      "title": "Sensitive credentials exposed in plaintext in Mattermost support packets",
      "x_generator": {
        "engine": "cvelib 1.8.0"
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  },
  "cveMetadata": {
    "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
    "assignerShortName": "Mattermost",
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    "datePublished": "2026-05-18T08:37:10.590Z",
    "dateReserved": "2026-04-15T10:50:45.853Z",
    "dateUpdated": "2026-05-18T14:37:17.045Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.