FKIE_CVE-2026-4055

Vulnerability from fkie_nvd - Published: 2026-05-21 08:16 - Updated: 2026-07-23 16:10
Severity
4.3 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Summary
Mattermost versions 11.5.x <= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629
References
responsibledisclosure@mattermost.comhttps://mattermost.com/security-updatesVendor Advisory
Impacted products
Vendor Product Version
mattermost mattermost_server *
mattermost mattermost_server *
mattermost mattermost_server *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
            {
              "lessThanOrEqual": "11.5.1",
              "status": "affected",
              "version": "11.5.0",
              "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"
            }
          ]
        }
      ],
      "source": "responsibledisclosure@mattermost.com"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "F9018E52-5C7F-4E59-B637-604B8EECD974",
              "versionEndExcluding": "10.11.17",
              "versionStartIncluding": "10.11.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "DF287562-A912-43DD-8FAC-0CD8EC7BEF7E",
              "versionEndExcluding": "11.5.5",
              "versionStartIncluding": "11.5.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "AFCFC389-02A5-45CD-8EEB-9ED208C0EE83",
              "versionEndExcluding": "11.6.2",
              "versionStartIncluding": "11.6.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Mattermost versions 11.5.x \u003c= 11.5.1 fail to validate team-level run_create permission against the target team when creating a playbook run which allows an authenticated team member to create runs in teams where they lack permission via specifying a different team ID in the run creation API request. Mattermost Advisory ID: MMSA-2026-00629"
    },
    {
      "lang": "es",
      "value": "Las versiones de Mattermost 11.5.x \u003c= 11.5.1 fallan al validar el permiso run_create a nivel de equipo contra el equipo de destino al crear una ejecuci\u00f3n de playbook, lo que permite a un miembro del equipo autenticado crear ejecuciones en equipos donde carecen de permiso mediante la especificaci\u00f3n de un ID de equipo diferente en la solicitud de API de creaci\u00f3n de ejecuci\u00f3n. ID de Aviso de Mattermost: MMSA-2026-00629"
    }
  ],
  "id": "CVE-2026-4055",
  "lastModified": "2026-07-23T16:10:00.137",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 4.3,
          "baseSeverity": "MEDIUM",
          "confidentialityImpact": "NONE",
          "integrityImpact": "LOW",
          "privilegesRequired": "LOW",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N",
          "version": "3.1"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 1.4,
        "source": "responsibledisclosure@mattermost.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-4055",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-05-21T12:39:26.946775Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-05-21T08:16:23.130",
  "references": [
    {
      "source": "responsibledisclosure@mattermost.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://mattermost.com/security-updates"
    }
  ],
  "sourceIdentifier": "responsibledisclosure@mattermost.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-863"
        }
      ],
      "source": "responsibledisclosure@mattermost.com",
      "type": "Secondary"
    }
  ]
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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