CVE-2026-9820 (GCVE-0-2026-9820)
Vulnerability from cvelistv5
Published
2026-07-13 10:51
Modified
2026-07-13 13:09
Severity ?
3.8 (Low) - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N
CWE
Summary
Mattermost versions 11.7.x <= 11.7.2, 10.11.x <= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671
References
Impacted products
Vendor Product Version
Mattermost Mattermost Version: 11.7.0   ≤ 11.7.2
Version: 10.11.0   ≤ 10.11.19
 Create a notification for this product.
Show details on NVD website

To clipboard 

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-9820",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-13T13:09:24.482863Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-07-13T13:09:31.383Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Mattermost",
          "vendor": "Mattermost",
          "versions": [
            {
              "lessThanOrEqual": "11.7.2",
              "status": "affected",
              "version": "11.7.0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "10.11.19",
              "status": "affected",
              "version": "10.11.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "11.8.0"
            },
            {
              "status": "unaffected",
              "version": "11.7.3"
            },
            {
              "status": "unaffected",
              "version": "10.11.20"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "0x7oda7123"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "Mattermost versions 11.7.x \u003c= 11.7.2, 10.11.x \u003c= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671"
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 3.8,
            "baseSeverity": "LOW",
            "confidentialityImpact": "LOW",
            "integrityImpact": "LOW",
            "privilegesRequired": "HIGH",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-862",
              "description": "CWE-862: Missing Authorization",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-13T10:51:34.023Z",
        "orgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
        "shortName": "Mattermost"
      },
      "references": [
        {
          "name": "MMSA-2026-00671",
          "tags": [
            "vendor-advisory"
          ],
          "url": "https://mattermost.com/security-updates"
        }
      ],
      "solutions": [
        {
          "lang": "en",
          "value": "Update Mattermost to versions 11.8.0, 11.7.3, 10.11.20 or higher."
        }
      ],
      "source": {
        "advisory": "MMSA-2026-00671",
        "defect": [
          "https://mattermost.atlassian.net/browse/MM-68824"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "Mattermost schemes teams endpoint exposes private team invite IDs",
      "x_generator": {
        "engine": "cvelib 1.8.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "9302f53e-dde5-4bf3-b2f2-a83f91ac0eee",
    "assignerShortName": "Mattermost",
    "cveId": "CVE-2026-9820",
    "datePublished": "2026-07-13T10:51:34.023Z",
    "dateReserved": "2026-05-28T11:26:12.173Z",
    "dateUpdated": "2026-07-13T13:09:31.383Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-9820\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-07-13T13:09:24.482863Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-07-13T13:09:27.579Z\"}}], \"cna\": {\"title\": \"Mattermost schemes teams endpoint exposes private team invite IDs\", \"source\": {\"defect\": [\"https://mattermost.atlassian.net/browse/MM-68824\"], \"advisory\": \"MMSA-2026-00671\", \"discovery\": \"EXTERNAL\"}, \"credits\": [{\"lang\": \"en\", \"type\": \"finder\", \"value\": \"0x7oda7123\"}], \"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 3.8, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"LOW\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:L/A:N\", \"integrityImpact\": \"LOW\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"NONE\", \"privilegesRequired\": \"HIGH\", \"confidentialityImpact\": \"LOW\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"Mattermost\", \"product\": \"Mattermost\", \"versions\": [{\"status\": \"affected\", \"version\": \"11.7.0\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"11.7.2\"}, {\"status\": \"affected\", \"version\": \"10.11.0\", \"versionType\": \"semver\", \"lessThanOrEqual\": \"10.11.19\"}, {\"status\": \"unaffected\", \"version\": \"11.8.0\"}, {\"status\": \"unaffected\", \"version\": \"11.7.3\"}, {\"status\": \"unaffected\", \"version\": \"10.11.20\"}], \"defaultStatus\": \"unaffected\"}], \"solutions\": [{\"lang\": \"en\", \"value\": \"Update Mattermost to versions 11.8.0, 11.7.3, 10.11.20 or higher.\"}], \"references\": [{\"url\": \"https://mattermost.com/security-updates\", \"name\": \"MMSA-2026-00671\", \"tags\": [\"vendor-advisory\"]}], \"x_generator\": {\"engine\": \"cvelib 1.8.0\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"Mattermost versions 11.7.x \u003c= 11.7.2, 10.11.x \u003c= 10.11.19 fail to sanitize team objects returned by the scheme teams endpoint, which allows a user with the User Manager role to obtain invite links for private teams and use them to join or share access to those teams via the scheme teams API endpoint.. Mattermost Advisory ID: MMSA-2026-00671\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-862\", \"description\": \"CWE-862: Missing Authorization\"}]}], \"providerMetadata\": {\"orgId\": \"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee\", \"shortName\": \"Mattermost\", \"dateUpdated\": \"2026-07-13T10:51:34.023Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-9820\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-07-13T13:09:31.383Z\", \"dateReserved\": \"2026-05-28T11:26:12.173Z\", \"assignerOrgId\": \"9302f53e-dde5-4bf3-b2f2-a83f91ac0eee\", \"datePublished\": \"2026-07-13T10:51:34.023Z\", \"assignerShortName\": \"Mattermost\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.